Electrochemical energy storage has the characteristics of high energy density, fast response time, low maintenance cost, flexible and convenient installation, and it is the hot development direction of energy storage technology in the future. In recent years, because of its low cost and high specific capacity, zinc ion battery has a good development prospects. The positive electrodes of aqueous zinc ion batteries are mainly vanadium-based compounds, manganese-based compounds and Prussian blue analogues; the negative electrodes are mainly zinc negative electrodes; the electrolytes include hydrogel electrolytes, ionic liquids, salt-coated electrolytes and electrolytes with additives.
However, for positive materials, the dissolution of Mn²⁺ in manganese compounds, the low discharge voltage of vanadium compounds and the low specific capacity of Prussian blue analogs all affect the performance of zinc ion batteries.The challenges faced by zinc electrodes as negative electrodes for zinc ion batteries include: (ⅰ) zinc dendrite growth, (ⅱ) continuous electrolyte consumption and self-discharge, (ⅲ) generation of irreversible by-products. Water decomposition and evaporation occur in the charging and discharging process of water electrolyte, which affects the performance of batteries. In recent years, researchers have been devoted to preparing new electrodes by doping other elements, surface coating and covering to improve the positive electrodes of aqueous zinc ion batteries. By modifying the interface, designing the three-dimensional structure of new zinc negative electrodes and designing and developing new electrolytes, the production of zinc dendrites can be reduced. At the same time, adding other solutions to the electrolyte can broaden the electrochemical window, so as to improve the electrochemical performance of aqueous zinc ion batteries.
At present, a new electrode material prepared by doping calcium, magnesium, cobalt and other elements into the cathode material and coating the surface with polypyrrole based polymer conductive polymer has been successfully applied. The appropriate proportion of metal ions doping can not only improve the material capacity, but also form a stable structure which is conducive to the deintercalation of Zn²⁺. The reversibility and stability of zinc anode can be improved and the growth of zinc dendrite can be inhibited by modifying the surface coating of titanium dioxide (TiO₂), gold nanoparticles and polyvinyl butyral (PVB) or adding appropriate additives in the electrolyte. These methods can directly or indirectly improve the cycle stability and coulomb efficiency of aqueous zinc ion batteries.
This paper first introduces the general situation of zinc ion batteries, and then focuses on the research progress of cathode materials, anode materials, electrolytes and separators, including the existing challenges and existing solutions. Finally, the future development of electrode materials, electrolytes and separators for aqueous zinc ion batteries is prospected, which provides ideas for the development and preparation of high-performance aqueous zinc ion batteries.

Aqueous zinc ion batteries (ZIBs), a new type of aqueous secondary batteries proposed in recent years, show great practical value and developmental prospects in the field of scale energy storage including electric vehicle and energy storage grid owing to their high energy density and high power density, safe and efficient discharge processes, cheap and nontoxic electrode materials and simple manufacturing process.
At present, one of the main factors hindering the further development of ZIBs is the lack of suitable cathode materials. Due to the large ion radius of Zn²⁺ and its hydrated ions, it will cause irreversible deformation or structural collapse of the cathode electrode material during insertion/desorption process, resulting in a rapid decline in battery capacitance. The poor conductivity of the cathode electrode material and serious electrode polarization during charging and discharging cause the charging voltage of cathode partially overlaps with the oxygen evolution voltage. As a result, the cathode electrode material will catalyze the water to produce oxygen, causing the battery flatulence to invalid during the charging process.Moreover, the strong electrostatic interaction between the divalent Zn²⁺ and the crystal structure of the cathode electrode material leads to unsatisfactory Zn²⁺ insertion capacitance. Therefore, it is crucial to develop a cathode material that can provide high capacity and maintain good structural stability during Zn²⁺ insertion/desorption process.
In view of the shortcomings of the cathode material of the ZIBs, a variety of modification methods are used to improve their performance: (Ⅰ) guest particles, such as metal ions, organic molecules and water molecules, are introduce in to the host so a more stable frame can be obtained through its structural changes; (Ⅱ) intrinsic mixed valence materials are prepared because of their better adaptability to the volume changes and valence changes of the cathode electrode material during charging and discharging; (Ⅲ) introduce oxygen vacancies to increase active sites to promote Zn²⁺ diffusion kinetics and increase material capacity; (Ⅳ) conductive materials are composed to improve the overall conductivity of the material and enhance structural stability; (Ⅴ) the nanostructure modification is carried out to enlarge specific surface area of cathode material, shorten the Zn²⁺ diffusion distance and increase the contact area of electrochemical reaction.
This article gives a brief introduction to ZIBs, its advantages and its energy storage mechanisms. Based on the key role of cathode materials in ZIBs, several common cathode materials such as manganese-based oxides, vanadium-based oxides, and prussian blue analogs are emphatically reviewed. Moreover, the structures, properties and defects of all above cathode materials are expounded, and the modification methods including doping guest particles, compositing with conductive materials, preparing intrinsic mixed valence states and constructing nanostructures are primarily discussed. At the end of this view, we pointed out several promising directions of the development of cathode materials for ZIBs.

With the aggravation of greenhouse effect, global warming and extreme weather emerge in endlessly,and efficient capture and storage of CO₂ become more and more imperative. At present, CO₂ capture technology mainly includes amine solution absorption and solid adsorption. Compared with the strong corrosiveness and environmental-unfriendly characteristics of the liquid absorption, the solid adsorbents have attracted wide attention due to their simple equipment requirements, low energy consumption and environmental friendliness properties. Among them, silica aerogel, with high specific surface area, high porosity, controllable pore size, easily modified surface, has aroused much interest in the field of CO₂ adsorption recently, which shows higher adsorption capacity of CO₂ than zeolites and activated carbons at low temperature.
There are two main factors affecting the CO₂ adsorption performance of silica aerogel. One is the structure characteristics of aerogel, including pore size, pore structure, specific surface area, porosity, etc. The other one is the number and distribution of functional groups on the surface of aerogel. Among them, the latter one plays a decisive role in the CO₂ adsorption property. A lot of studies have been carried out around the modification of silica aerogel. Currently, amino acid functionalization and nitrogen doping are used to introduce alkaline sites, which greatly improve the adsorption performance of SiO₂ aerogel to CO₂. However, the influence of the selection of organic amines and their carrying capacity, as well as the proportion of micropores /mesopores/ macropores in the adsorbent on the adsorption performance of CO₂ have not been clarified yet. Therefore, the design of pore structure of modified SiO₂ aerogel and the regulation of distribution of alkaline sites has become the key issue to further improve the adsorption property of CO₂. Meanwhile, improving adsorption rate, optimizing preparation process and reducing production cost are also the emphases of future research work.
In this paper, the influence of preparation technology of silica aerogel on its microstructure is reviewed, while the amino modification method of aerogel and the related adsorption mechanism during the adsorption process are concluded. In addition, the research progress of CO₂ adsorption by silica aerogel is summarized and the existing problems are pointed out, which provide scientific and practical reference for improving the adsorption performance of CO₂ on silica aerogel.

The safety problem caused by material defects has always been a hot issue, and how to realize the rapid accurate identification and location of material defects is the focus of current research on material defects. The traditional non-destructive testing method mainly uses ultrasonic, X-ray and other advanced technologies to realize the identification and positioning of material defects. Although this method solves the problem of low manual testing efficiency, it is still difficult to achieve the requirements of intelligentization, automation and high precision.
Advances in the computer technology has stimulated the rapid development of machine vision in the detection of material defects. The advantages of machine vision inspection technology are mainly the combination of non-destructive inspection, automation and intelligentization, which has not only good safety and high efficiency, but also high detection accuracy. However, an image processing algorithm usually can be effective to the recognition of only one specific kind of defect, which causes low versatility of the equipment and elevated cost of production and maintenance.
In recent years, the rise of deep learning has promoted the rapid development of the field of artificial intelligence, and solved the problem that traditional machine vision needs different image processing algorithms to classify different tasks. Deep learning has also become a popular research direction in material defect detection. Many scholars have applied deep learning technology to the field of material defect detection, and they have achieved good results whether they are related to the classification of material defects, or the location and the segmentation of material defects.
The article summarizes the application of traditional methods and machine vision methods in material defects, introduces the principles of deep learning in material defect detection, and systematically describes the application of deep learning in the classification, positioning and segmentation of material defects at home and abroad, and the future development trend of the application of deep learning in the field of material defect detection is prospected.

Monoclinic gallium oxide (β-Ga2O3) is an emerging wide bandgap semiconductor with an ultrawide bandgap (~4.9 eV) at room temperature, an high breakdown field strength (~8 MV/cm), a Baliga's figure of merit (BFOM) of 3 400, and availability of native single crystal substrates using inexpensive melt-based growth methods. These attractive properties of β-Ga2O3 make it an ideal candidate for potential applications such as high-power electronic devices and solar blind ultraviolet (UV) photodetectors. It is well known that the high quality epitaxial layer is the prerequisite for the fabrication of high performance devices. Up to now, the β-Ga2O3 epitaxial layers have been prepared by various methods, and several kinds of devices have been fabricated. However, many challenges still exist, including heteroepitaxial growth maturity, p-type doping, and device performance optimization. This article reviews the current status of the synthesis technologies, the substrates for homoepitaxy/heteroepitaxy, doping, electrical properties and the applications of power devices and ultraviolet photodetectors.

The waste tire rubber powder made from waste tires can be used to prepare rubber asphalt, which can realize the resource utilization of waste tires in pavement. In this work, asphalt samples modified by waste tire rubber powder with different aromatic oil contents, reaction temperatures and reaction times were prepared. The solubility test was designed and combined with scanning electron microscope (SEM) test to study the correlation between the reaction degree of rubber powder and the storage stability. The change trends of penetration, ductility, softening point, elastic recovery and high temperature viscosity indexes of rubber asphalt in the reaction process were tested, and the index values were compared with those of matrix asphalt, SBS modified asphalt and medium/high content rubber asphalt without aromatic oil, so as to determine the preparation parameters of high content rubber asphalt with aromatic oil. The results show that adding aromatic oil effectively improves the storage stability of 35% rubber asphalt and ensures its workability of construction. Rutting factor ratio is more suitable to evaluate the storage stability of high content rubber asphalt than softening point difference index. The solubility of high content rubber asphalt has an obvious correlation with its storage stability. The addition of aromatic oil has an adverse effect on high and low temperature performances of 35% rubber asphalt, but when the content of aromatic oil is within 5%—7.5%, its high and low temperature performance is still close to SBS modified asphalt. The preparation parameters of high content waste tire rubber asphalt can be determined as follows: the shear speed is 800 r/min, the content of waste tire rubber powder and aromatic oil is 35% and 5%—7.5% of the total mass of rubber asphalt respectively, the reaction temperature is 230 ℃, and the reaction time is 225 min.

As the most widely used secondary battery at present, lithium-ion batteries (LIBs) with graphite anode cannot meet the increasing demands for high energy density storage systems in consequence of the low theoretical capacity of graphite (372 mAh/g). Among all anode candidates, metallic Li has been regarded as the most promising anode for the next generation rechargeable batteries, due to its ultrahigh theoretical capacity of 3 860 mAh/g and its lowest redox potential (-3.04 V, versus standard hydrogen electrode). Especially, when Li is coupled with high-energy non-Li-containing cathodes such as S and O₂, the assembled Li-S and Li-O₂ batteries boast a much higher energy density than LIBs, thus deserving to be intensively investigated.
However, low Coulombic efficiency and poor stability have been crucial factors limiting the commercial application of lithium metal batte-ries (LMBs). When directly used as the negative electrode, metallic Li is easy to react with electrolytes, forming a chemically unstable and mechanically fragile solid electrolyte interphase (SEI) between them. The repeated rupture of SEI caused by the drastic volume expansion of anode du-ring continuous cycling will induce the dendrites growth and ‘dead Li' formation, leading to irreversible capacity loss. Furthermore, when lithium dendrites grow to a certain extent, they will penetrate the separator, resulting in cell shorting or even explosion, thus causing serious safety ha-zard.
Extensive efforts have been devoted to dealing with the issues mentioned above, including failure mechanism exploration, structure design and interface enhancement of lithium metal anode. Some advanced technologies, such as introducing 3D, surface modified current collectors and building in-situ/artificial SEI on lithium anode, are effectively applied to inhibit the dendrite growth and alleviate the volume effect based on the widely accepted theoretical models like Chazalviel-Brissot model, Yamaki model and electrostatic shielding model.
This review systematically introduces several typical failure mechanisms of lithium metal anodes and emphatically summarizes the recent key progress in structure design and interface enhancement strategies of lithium metal anode. After analyzing the remaining challenges, some suggestions are also provided to accelerate the commercialization of LMBs.

Ferroelectric materials are an important class of functional materials with spontaneous polarization in a certain temperature range. Their spontaneous polarization can be reversed by an external electric field, and they have a wide application potential in electronic devices such as photovoltaic regulators and storage. At present, the development of ferroelectric materials for applications is severely constrained by their high resistance and low carrier concentration, so there is an urgent need to find a simple and effective method to optimize the ferroelectric properties and other physical properties of ferroelectric materials. Pressure control is an effective means to modulate the crystal structure and electronic configuration and regulate the physical properties of materials. Lower pressure can affect the balance between long-range Coulomb attraction and short-range electron repulsion in ferroelectrics, resulting in an obvious increase in short-range repulsion and a decrease in ferroelectricity. However, once the critical pressure is reached, the ferroelectricity begins to increase, and the ferroelectric phase transition occurs, thus changing the physical properties of materials. In recent years, the research on the structure and physical properties of ferroelectric materials regulated by pressure at home and abroad mainly focuses on exploring ferroelectric phase transition and other physical properties of materials caused by pressure, and exploring its internal influence mechanism.
As an important dimension to adjust and control the structure of ferroelectric crystals, pressure can replace doping to study the ferroelectric phase transition to some extent, and it can also stabilize the phase transition temperature. The improvement of dielectric and ferroelectric properties of materials due to domain wall change and de-aging process caused by high pressure can make the materials well applied in device equipment. Pressure can modulate the relaxation behavior of ferroelectric materials by affecting the polar nano-domains, and it can also change the magnetic sequence or symmetry of the magnetoelectric coupling material to change its ferroelectric properties. The synchronous enhancement of ferroelectric, electric transport and photoelectric properties can be realized in the high pressure phase of ferroelectric photovoltaic materials, relative to those in the low pressure phase, and the mechanism of ferroelectric photovoltaic can be further explored by means of high pressure.
This review summarizes the high pressure research progress of ferroelectric materials at home and abroad, discusses the structural evolution of ferroelectric materials under high pressure and its occurrence mechanism, and the influence of high pressure conditions on ferroelectric properties, dielectric properties, relaxation behavior, magnetoelectric coupling and photovoltaic properties of ferroelectric materials is introduced. These provide new ideas for the research and design of new high-performance ferroelectric materials using high pressure technology.

Reversible solid oxide cell (RSOC) is an energy conversion device with high efficiency of reversible power generation and electrolytic hydrogen generation, which is considered as a new energy conversion device with good development prospects. However,there are still some technical problems to be solved, as the lack of highly active and stable electrode materials currently limits the wide application of RSOC. Traditionally, the fuel electrode generally uses nickel-yttrium-stabilized zirconia (Ni-YSZ) materials, while there are many types of oxides that can be used as the oxygen electrode. The electrochemical properties of both fuel electrodes and oxygen electrodes have to be further improved. In recent years lots of works reported that SrTiO₃-based perovskite material is a typical of electrode material with good performance in RSOC, which has become a popular candidate material to solve the RSOC electrode problem. However, there is a lack of systematic summary of this kind of materials. Therefore, the application progress of SrTiO₃-based perovskite materials as the RSOC electrode is reviewed in this paper. Firstly, the study of SrTiO₃-based perovskite materials used as RSOC fuel and oxygen electrodes is systematically analyzed, and the methods and measures commonly used for SrTiO₃ modification, such as doping, nonstoichiometric ratio, recombination and a new method: in situ precipitation, are introduced. Secondly, the feasibility of applying SrTiO₃-based perovskite for RSOC electrodes with a symmetrical structure is discussed. Finally, from the perspective of the construction of a new generation of high-performance RSOC for energy internet in the future, the application prospect and the problems to be solved of SrTiO₃-based perovskite materials in RSOC are predicted.

Ultra-high temperature porous ceramics (UHTCs) exhibited a fascinating combination of properties of porous ceramics including high porosity, high specific surface area, as well as beyond satisfactory physicochemical and high-temperature stability and properties of UHTCs including good high temperature volume stability, outstanding oxidation/ablation resistance, which make it as an appropriate candidate for applications under severe environments, such as high-temperature thermal insulation components, high-temperature hostile gases filtration, high-temperature solar absorptions, etc. Ultra-high temperature porous ceramics have been fabricated by partial sintering, replica, sacrificial template, freeze casting, direct foaming and sol-gel method, based on the different pore-forming mechanism. The ultra-high temperature porous ceramics prepared by partial sintering method had excellent mechanical properties, but its porosity was low, and pore structure was non-uniform. Because the pore morphology of porous ceramics prepared by replica method was inherited form the pore structure of templates, the porous ceramics had high porosity and poor designability for pore structure. The pore size and microstructure of ceramic materials prepared by sacrificial template method can be tailored, but porous ceramics had non-uniform pore size distribution. Porous ceramics prepared by freeze casting, which had emerged as a high-efficiency, low-cost and high porosity; however, its fabricating process was not environmentally friendly due to organic solvents were used as freezing vehicles. The porous ceramics prepared by direct foaming method possessed high porosity and homogeneous pore structure, but the foaming process in a tailored manner was difficult. The ceramic materials prepared by sol-gel method had high porosity, low thermal conductivity, low strength and highcost. In this paper, the preparation, properties and future application of ultra-high temperature porous ceramics were comprehensively reviewed. The advantages and disadvantages of the fabrication of porous ceramics were summarized. The problems and outlook of ultra-high temperature porous ceramic materials were proposed, which aimed to provide guidance for the preparation of ultra-high temperature porous ceramic materials.

Catalytic purification has been developed to be a main technology involving with the removal of environmental pollutants. Microwave (MW) radiation with excellent performances of volatility, high frequency, thermal and non-thermal characteristics has caused widely attention. Therefore, MW-induced catalytic reactions play a vital role in improving environmental quality. With the continuous in-depth research of MW radiation and catalytic technology, the development of multifunctional materials with excellent MW absorbing performance and catalytic activity has become the focus of studies.
According to the way of transforming the MW, wave-absorbing materials can be divided into three types, including dielectric loss, resistance loss and magnetic loss.The absorbing performance of the wave-absorbing materials is affected by various factors such as element composition, surface configuration and pore structure. In recent years, researchers have been improving the synthetic methods of wave-absorbing materials from the matching and attenuation characteristics, and have achieved substantial progress in enhancing the MW absorbing properties of mate-rials, and making full use of MW-induced catalytic reactions to improve the energy utilization rate as well as the degradation rate of environmental pollutants.
Wave-absorbing materials will produce hot spot effect and discharge effect in the MW field. The MW-induced catalytic reaction changes the conventional thermal field to MW heating, which can realize the rapid temperature rise of the material at a lower environment temperature and achieve excellent catalytic performance. Metal materials can induce MW discharge in the MW field, and the discharge process will produce thermal effect, plasma effect and photocatalytic effect, which plays a crucial role in pollutant removal. However, since the reaction process of MW-induced cata-lysis is complicated, current studies have focused on distinguishing the influence of heat spot effect and discharge effect and clarifying the reaction pathway of MW-induced catalysis. Over the past years, a variety of catalysis with outstanding wave-absorbing and catalytic performances has been developed, and applied the MW-induced catalytic reaction to the purification treatment technology of waste water and exhaust gas, which has the advantages of fast reaction rate and high treatment efficiency.
This paper mainly introduces the principle of MW absorption of materials, expounds the improvement of MW absorption properties of materials and the application of MW hot spot effect and discharge effect in pollutant removal, and discusses the future development direction of MW-induced catalytic reactions.

Thermoelectric material is a kind of functional material, which realizes the mutual conversion between thermal energy and electrical energy. It can recycle waste heat generated in the process of fossil fuel combustion and industrial production, and shows good application prospects in small thermoelectric generators, solar cells, and smart sensors, etc. Thermoelectric materials are gradually applied to small wearable devices with the development of modern technology, which puts forward new requirements for safety, non-toxicity, stable high conversion efficiency and flexibility of thermoelectric materials. Compared with electronic thermoelectric materials, ionic thermoelectric materials have the advantages of high Seebeck coefficient, flexible stretchability, low toxicity and low pollution, and have good application potential in both thermoelectric power generation devices and small wearable devices. In this paper, the research progress of ion gel-based thermoelectric materials in energy harvesting devices such as thermogenic batteries and ionic thermoelectric capacitors are discussed. The problems and challenges faced by ionic thermoelectric materials in the application of wearable energy conversion devices are analyzed, in order to provide new directions for the preparation of safe, pollution-free, stable and efficient new flexible wearable devices.

Icing is a quite common natural phenomenon in our daily life. However, undesired ice accretion causes a series of adverse effects on indivi-dual and public activities, and sometimes paralyzes traffic and transportation system, or even power generation and supply system, resulting in enormous economic losses and safety issues. Traditional methods for solving icing problem are based on active processes, mainly including mechanical deicing, heating, chemical treatment, etc. And these strategies are either time consuming, environmentally hazardous, costly or inefficient. In the last decade, designing and deploying materials that can assist the removal of ice have received growing interests. Inspired by creatures such as lotus leaves and pitcher plants, people have created superhydrophobic coatings and slippery liquid-infused porous surfaces (SLIPSs) to prevent freezing behavior on the surface of materials. In addition, the anti-icing mechanism of antifreeze proteins have been explored by studying organisms in the cold zone, which paves a new approach for the novel design of biomimetic anti-icing polymer materials. In this review, we firstly give a fundamental introduction on the mechanism and performance requirements of anti-icing materials, as well as the apparatus for testing the ice adhesion strength. Then we discuss the advantages and drawbacks of currently existing anti-icing surfaces, e.g. superhydrophobic coatings, lubricating coatings, antifreeze proteins and stress-localized surfaces. Finally, we share our prospective views on potential applications and future development trends of artificial anti-icing materials.

High-performance carbon fiber has great application prospects. The carbon content of carbon fiber can reach 99% after graphitization. The tensile modulus and conductivity can be improved greatly, and the coefficient of thermal expansion approaches to 0, which is suitable for the space environment involving a great diurnal temperature variation. Therefore, graphitized carbon fiber is extensively applied to cutting-edge technology fields such as space flight and aviation. Graphitization equipment and methods are the key aspect for preparing high-performance carbon fiber. In this paper, graphitization equipment is divided into continuous and discontinuous, indirect heating and direct heating, according to production process and heating method. Introductions were given to graphitization techniques including resistance heating, induction heating, plasma heating, microwave heating, laser heating, γ-ray heating and catalytic heating. In addition, the advantages and disadvantages of graphitization methods and equipments were summarized, meanwhile the microstructure change of carbon fiber in graphitization and its correlation with carbon fiber properties were analyzed. It will be the future development trend to optimize the traditional graphitization equipment and overcome the disadvantages of existing graphitization equipment such as high energy consumption, high cost and low efficiency. It provides important reference and experience for the future research and development of emerging graphitization process, equipment and the preparation of graphite fibers with complete structure and excellent performance.

In recent years, flexible electronic technology has broken through the limitation of traditional electronic devices, which has been widely applied in the fields of electronics, energy, medical care, information technology, national defense, etc. As the basic structural unit of flexible electronic devices, metal film/compliant substrate systems inevitably suffer from various deformation in the practical application, such as tension, compression, bending and torsion. Thus, it is a big challenge to prepare the material systems, design the film/substrate interfaces and optimize the structures for maintaining the structural stability of metal film/compliant substrate systems.
Polydimethylsiloxane (PDMS) is often used as the substrate material for flexible electronics. However, the PDMS substrates cannot effectively suppress the strain localization of the metal films because of low elasticity modulus and poor adhesion. The as-deposited metal films may even fracture, restricting the development of flexible electronics. Recently, much effort has been devoted to the deformation and fracture behavior of metal films on PDMS substrates. Some strategies have been proposed to improve the stretchability, including optimizing the film preparation, enhancing the interface adhesion, and designing the geometries of the films and substrates.
For example,the stress state of metal films can be tuned by changing deposition parameters. A compressive stress in metal films is beneficial to the stretchability. The stretchability can also be improved by interfacial adhesion strategies, such as ultraviolet-ozone (UVO) treatment, oxygen plasma treatment, and adding adhesion interlayers. However, the improvement of the stretchability is considerably limited by optimizing film preparation and enhancing interface adhesion. Recent studies have demonstrated that the stretchability would be significantly improved by introducing the wrinkling/buckling structures in films or substrates, which provides a possibility for the practical application of flexible electronics. Additionally, as one of the most common failure modes of metal thin films, cracking will remarkably impair the stretchability, which usually should be avoided. On the contrary, it is helpful to achieve some functionalities by controlling the fracture behavior of the metal films. For example, it has been demonstrated that the highly sensitive flexible strain sensors can be developed by manipulating the cracking behavior of metal thin films.
This review summarizes the research progress of deformation and fracture behavior of metal films on PDMS substrates, and introduces the strategies for improving the stretchability, including optimizing film preparation, modifying the PDMS surface, adding the adhesion interlayers and designing wrinkling/buckling structures. By analyzing the current challenges and future opportunities, this review is expected to provide the theoretical reference for the preparation of optimization and structural design of high-performance flexible electronic devices.

This paper focuses on the research achievements of our laboratory in the last 20 years in the field of long-persistent luminescence materials. Starting from the key issues of long persistent luminescence materials, this paper makes a detailed analysis and summary of the matrix selection of materials, the exploration methods of doping and solid solution, the discussion on the mechanism of material lasting glow, and the extended research on special lasting glow phenomena. The future research direction of long-persistent luminescence materials has also been prospected. The future research direction of long-persistent luminescence materials has also been prospected, which is purpose on providing a reference for researchers in this field.

Organic-inorganic hybrid perovskite materials have been widely used in the area of photovoltaic, display devices and sensors because of their excellent photoelectric properties. In recent years, the key technology of perovskite solar cells (PSCs) has developed rapidly, and there are many breakthroughs that have been made in photoelectric conversion efficiency and devices area. However, the stability of perovskite mate-rials and devices has not been fundamentally solved, which seriously restricts the practical performance and commercialization of perovskite photovoltaic devices. The instability of PSCs derived from the perovskite active layer, the charge transport materials and the electrode materials. The causes mainly include environmental factors such as light, water, temperature and oxygen. Therefore, it is crucial to understand the mechanism of each factor on the stability of PSCs. In addition, compared with crystalline silicon solar cells and other thin-film solar cells, PSCs have great differences in material properties and device structures. At present, the stability evaluation methods and testing methods of crystalline silicon cells and other thin film cells are not fully applicable to PSCs. A standard stability tests procedure is required in order to compare the stability test results of perovskite cells between the various institutions.
In this paper, the factors affecting the stability of perovskite materials and photovoltaic devices are firstly summarized. Then the mechanism of environmental factors such as light, moisture, temperature and oxygen on the stability of perovskite devices are analyzed, and the methods to improve the stability of PSCs are summarized. Finally, the stability evaluation and testing methods, as well as the future development direction of PSCs are analyzed and forecasted, which provide a new idea for the commercial application of PSCs.

Thermal control material is an important medium to realize the thermal control function of spacecraft, and is the basis for the development of spacecraft thermal control technology. The wide application of multilayer insulation materials, thermal conductive materials, thermal coatings and interface materials in the spacecraft thermal control system, realize the thermal control of spacecraft by using the thermophysical properties of the materials. From the perspective of spacecraft thermal control materials engineering application, we summarize the research and application progresses of four types of thermal control materials commonly used in spacecraft thermal control system, including thermal insulation materials, high thermal conductivity materials, coating materials and interface materials, and prospect the development needs of thermal control technology in deep low and high temperature environment, which will be applied in the future space science probe and low temperature propellant in-orbit storage project. Finally, we put forward suggestions on thermal control materials that may be used in deep low and high temperature environment, such as high thermal insulation materials and coating materials.

Due to the ultra-thin and flexible layered structure, two-dimensional (2D) materials are expected to break through the limitation of traditional resistive materials in reducing memristor size,and thus become the research hotspot in the field of resistive memory, flexible electronic device, neuromorphic computing, etc. In this paper, the research progress of 2D-materials-based memristors is reviewed from the aspects of device structure, material type, switching mechanism, electrode, functional layer modification, etc. The sandwich-structure is the most commonly used structure for memristor, and its device switching performance can be improved by inserting regulating layer. Although planar-structure memristor shows poor switching properties, it has advantage of easy observation and is conducive to the investigation of switching mechanism. Graphene and its derivatives are the most widely studied 2D memristive materials, as well as molybdenum disulfide. The application of other 2D materials (such as WS₂, MoTe₂, h-BN, black phosphorus, MXene, perovskites, etc.) in memristors and their switching performances have also been summarized and analyzed. The device switching mechanisms mainly include conductive filaments, charge trapping/detrapping and atom vacancy. It is found that the interfacial barrier and charge transport can be effectively controlled by selecting the electrode with appropriate work function. Besides, the dispersion of the device switching performance can be reduced by combining the 2D material with polymer or nanoparticles. What still needs hard work is to engineer the interfacial properties, especially under bending conditions or extreme temperatures. New and preferable 2D memristive materials need to be further explored to realize industrial application.

Diamond/copper composites show great prospect in thermal management applications due to their high thermal conductivity(TC) and low coefficient of thermal expansion (CTE) in theory. However, the actual TC is far below the theoretical TC, because of the poor interface affinity between diamond and copper. At usual atmospheric pressure, even the molten cooper can not wet the diamond. So the gaps with the high thermal resistance usually can be found between diamond and cooper. Optimized sintering and interface control techniques are usually used to improve the actual TC of diamond/copper composites (Dia/Cu). In this paper, the sintering techniques such as high temperature and high pressure, vacuum hot-pressing sintering, spark plasma sintering and infiltration are summarized. The bonding of diamond/copper interface can be strengthened by adding metal elements into copper matrix and surface metallization of diamond. Moreover, the problems of diamond/copper composites preparation and interface modification are pointed out, as well as the development trend.

Transparent conductive oxides (TCOs) are heavily-doped semiconductor materials, which are widely used in the fields like liquid crystal displays, touch screens and solar cells. They exhibit a high conductivity close to that of metal, because of a large number of free electrons produced by heavy doping and high degeneracy. Moreover, TCOs maintain larger band gap, which provides high visible light transmittance. As a kind of TCOs material, indium tin oxide (ITO) thin film has excellent photoelectric properties, such as wide band gap, high visible light transmission, high near-infrared reflection and low resistivity. Therefore, ITO thin film becomes the most widely used TCOs in the world, with a market share of 97%.
At present, ITO thin film still has some shortcomings to be solved, such as higher cost of Indium. Moreover, ITO show poor light transmittance in the near-infrared region and brittleness, which cannot meet the requirements of modern optoelectronic devices for flexibility. With the development of science and technology and the upgrading of various electronic components, ITO thin films can no longer meet the needs of applications nowadays. How to further improve the properties of ITO thin films has become a hot research topic.
Element doping can improve the overall performance of the ITO thin film. For example, free electrons will be generated by the inequivalent replacement of high-valent metal elements. The photoelectric properties of the thin film can be enhanced by optimizing carrier concentration, carrier mobility and scattering mechanism. The mechanical properties also can be modulated by introducing impurity elements, which inhibit surface migration, the crystallization and reduce internal stress of the thin film. In addition, element doping can promote the formation of passivation layer and stable chemical bonds to deal with harsh working conditions, such as high temperature, high pressure and strong corrosive environment.
This article summarizes the research progress of element-doped ITO thin films. The effects of element doping on photoelectric properties, mechanical properties and stability of ITO thin films are introduced, respectively. Moreover, this review discusses the existing problems in current research, and the development direction of element doping in ITO thin films.

In recent years, with the discovery of single-layer graphene, two-dimensional (2D) materials have gradually attracted people's attention. Among them, two-dimensional transition metal dichalcogenides (TMDs) have been widely studied and achieved many results due to their unique structure and photoelectric properties. Platinum disulfide (PtS₂), a two-dimensional material, has attracted extensive attentions because of its adjustable band gap (0.25 eV in the bulk layer to 1.75 eV in the monolayer) and high mobility (1 000 cm²·V^-1·s^-1). In this paper, the atomic structure and other basic characteristics of PtS₂ are introduced. The main preparation methods of PtS₂, such as mechanical stripping and chemical vapor deposition (CVD), are summarized. The physical properties of PtS₂, such as energy band structure and lattice vibration, are analyzed. Finally, the existing problems of PtS₂ are analyzed and discussed, and its further development in the future is prospected.

Water shortage, environmental pollution and energy crisis have been the global issues with the fast development of economic society. It is a green and sustainable solution to generate clean water from seawater and wastewater by distillation and separation with abundant solar energy. However, the traditional way of solar purification via heating the whole liquid has extremely low photo-thermal efficiency of 30%—45%, which calls for expensive equipment and frequent maintenance, whose practical applications are limited greatly. Recently, interface solar evaporation is a cost-efficient and environmental purification technology via heat location on the surface of evaporator, whose evaporation efficiency is much higher than that of the traditional way. This technology is a promising strategy to address the problem of water crisis in future and be applied in seawater desalination, distillation separation and power generation.
In this review, the mechanism of photothermal conversion in interfacial solar evaporation technology is introduced, and the progress of photothermal conversion materials, evaporator structure design and thermal energy engineering management in solar evaporation technology is briefly described. The current development of interfacial solar evaporation in the areas of seawater desalination, water purification, solar distillation-cogeneration, sterilization and other energy generation is reviewed.The bottleneck problems encountered in practical application of this technology are summarized, and the development trend of interfacial solar evaporation technology is prospected. Interfacial solar evaporation technology is of great significance for solving water shortage and energy crisis.

The production and the stockpiling of scrap tires have continued to increase in recent years. Such a vast amount of scrap tire not only occupies farmland but also causes environmental pollution problems. Hence, the ‘Black Pollution' caused by scrap tire has attracted much attention. Scrap tire is considered an ideal material for road construction due to its properties of light weight, high strength, and resistance to high temperature and corrosion, as well as coordinated utilization with other solid wastes. This paper presents a review of the literature on structure composition and mechanical and creep properties of scrap tire. The utilizations of scrap tire as road material in pavement, subgrade and foundation reinforcement are introduced. The working mechanism and the road performance of resource utilization technologies for scrap tires are summarized. Finally, the future development trend and key research directions of utilization technologies for scrap tire in road construction engineering are prospected.

The emergence of nanozymes is a major advancement in the research field of artificial enzymes, breaking through the limitations of previous artificial enzymes with low catalytic efficiency. It has been widely used in many fields, such as disease diagnosis and treatment, environmental monitoring and sewage treatment. In recent years, a variety of nanomaterials with natural enzymatic activity have been discovered, and nanomaterials with peroxidase-like activity have been used to prepare colorimetric biosensors. With the help of the catalytic ability of nanomaterials, the simulation of peroxidase-like activity can be achieved. Taking advantage of its advantages of low cost, high stability and easy storage, the catalysis of biochemical reactions can be directly realized. Therefore, the rapid and sensitive qualitative and quantitative analysis of the target can be achieved by naked eye observation or with a spectrophotometer.
The application of nanomaterials with peroxidase-like activity in colorimetric sensors provides a broader space for the development of new nano-colorimetric sensors. However, as the research expanded,this type of nanomaterials also exposed some problems that needed to be improved, such as specific pH requirements, insufficient affinity and insufficient catalytic activity. In view of these problems, most researchers have focused on the improvement and optimization of materials. Existing research shows that the performance can be improved and enhanced by changing the structure of the material, increasing the surface modification and using composites of various nanomaterials. This review clarifies the color-rendering mechanism of the colorimetric sensor. Then, the research progress and application of peroxidase-like nanozymes are reviewed in detail from the perspective of six types of nanomaterial (precious metal nanomaterials, metal oxide nanomaterials, metal sulfide nanomaterials, carbon-based nanomaterials, metal organic frameworks and MXene nanomaterials). Finally, the current challenges faced in the application of peroxidase-like nanozymes are summarized and discussed, and the status and future development prospects of nanomaterials in colorimetric analysis are elucidated.

Diatomite has gradually become one of the hotspots in the interdisciplinary research by virtue of its natural three-dimensional mesoporous and bionic structure, low synthesis cost and other advantages. However, the main component of diatomite is amorphous SiO₂, whose high resistivity greatly limits its application in electronic devices. Through the modifying process, diatomite can be converted into diatom-based silicon with high conductivity while maintaining the original structure, thereby promoting its application in electronic devices. The magnesiothermic reduction has attracted wide attention because of its simple operation, low cost and pollution-free. In order to promote the yield and performance of silicon and reduce the generation of intermediate products such as Mg₂SiO₄ and Mg₂Si, researchers have experimented on the reaction temperature, the reaction time, the mixing mode of the silicon source and the magnesium source, the molar ratio of the raw materials, the moderator, the variety of raw materials, etc. Finally, the optimal range of parameters such as reaction temperature and reaction time are determined, which promotes the efficient large-scale preparation of diatom-based silicon.
Diatom-based silicon prepared by magnesiothermic reduction has been greatly developed and applied for electronic devices such as lithium batteries, supercapacitors and solar cells due to its excellent structural stability,large specific surface area, natural microporosity and so on. Moreover, it can be used as the negative electrode of lithium-ion batteries, effectively solving the problem of volume expansion during charging and discharging. The preparation of diatom-based silicon is simpler, compared with other nanostructures, and it has higher capacity and cycle stability after further loading electrochemically active materials. Besides, the high porosity of diatom-based silicon facilitates the adsorption and deposition of electrochemically active materials, giving it significant advantages in the application of supercapacitors and solar cells; in addition, it has unique application of biomedicine because of excellent biocompatibility and luminescence properties.
This paper summarizes the development and improvement of the magnesiothermic thermal reduction of diatomite, and the research status of the application of diatom-based silicon in various electronic devices (lithium ion batteries, supercapacitors, solar cells, biosensors, etc.). Finally, the development trend of the preparation of porous silicon from diatomite by magnesium thermal reduction is prospected.

La-Mg-Ni system hydrogen storage alloy is considered to be one of the most promising anode materials for nickel-hydrogen battery due to its high discharge capacity, high energy density and good rate performance. However, the La-Mg-Ni system hydrogen storage alloy has the disadvantages of difficult preparation and poor cycle stability, which seriously hinder its practical application. Therefore, how to optimize the preparation process and improve the cycle stability of the La-Mg-Ni system hydrogen storage alloy is the primary problem to be solved. The related research has important academic value.
Generally speaking, La-Mg-Ni system hydrogen storage alloys mainly include three crystal structures, AB₃-type, A₂B₇-type and A₅B₁₉-type. Each of the three crystal structures is stacked with one AB₂ unit and one or more AB₅ units along the c axis. The actually prepared La-Mg-Ni system hydrogen storage alloy usually contains a multi-phase structure, and its performance is closely related to the structure of the alloy, while the structure of the alloy is closely related to the preparation process of the alloy. When the La-Mg-Ni system hydrogen storage alloy is prepared by the conventional smelting method, since the melting point and the boiling point of Mg are much lower than that of other alloy components, Mg is very easy to volatilize at high temperature during the smelting process. In addition, the volatilization of Mg makes it difficult to control the reaction, and the alloy composition is inaccurate, which seriously affects the performance of the alloy. Therefore, researchers have tried preparing La-Mg-Ni system hydrogen storage alloys by advanced preparation methods such as ball milling, melt spinning, high pressure sintering, co-precipitation-reduction diffusion method, etc. At the same time, researchers have also tried combining a variety of methods to prepare La-Mg-Ni system hydrogen storage alloys. The influence of the preparation process on the alloy phase structure and its electrochemical performance has also been studied. In recent years, there have been most studies on the combination of two or more preparation processes to prepare La-Mg-Ni system hydrogen storage alloys. It is found that the combination of multiple preparation methods can also significantly improve the electrochemical properties of the La-Mg-Ni system hydrogen storage alloy, especially annealing treatment effectively improving the cycle stability of the La-Mg-Ni system hydrogen storage alloy.
The superlattice phase structure in the La-Mg-Ni system hydrogen storage alloy is firstly introduced in this paper. Then, different preparation processes of La-Mg-Ni system hydrogen storage alloys at home and abroad in recent years are focused, including melting, mechanical alloying, sintering, melt-spinning and subsequent treatment of materials. The microstructure and the electrochemical performance of the alloys prepared by different preparation techniques are explored. At the same time, various preparation methods are comprehensively reviewed, providing ideas and basis for the research on how to prepare La-Mg-Ni system hydrogen storage alloys with excellent properties. Finally, the future development trend of La-Mg-Ni system hydrogen storage alloys is analyzed and prospected.

Due to its special optical properties, fluorescent materials have been widely used in biomedicine, biological imaging, fluorescence sensing and other related fields. Compared with traditional fluorescent agents, nano-fluorescent materials have the advantages of good stability and high fluorescence intensity. However, traditional semiconductor nano-fluorescent materials often contain heavy metals, which limits their application in biomedical fields. As a new type of fluorescent carbon nanomaterials, biomass fluorescent carbon dots (CDs) have some favorable characteristics such as biocompatibility, chemical inertness and fluorescence regulation, which have potential applications in biomedicine, biosensor, fluorescence imaging and other fields. At present, there are relatively few studies on the application of biomass CDs in biomedicine field. Therefore, this article summarized the green synthesis methods of different natural products to prepare CDs, and analyzed the fluorescence mechanism of CDs. It focused on the application of CDs in biomedical fields such as biosensors, biological imaging, drug carriers and biological antibacterial agents, discussed the existing problems, and looked forward to its future development direction in this field.

Metal-organic frameworks (MOFs) are ordered network complexes formed by the connection of metal ions with organic ligands coordination bonds, demonstrating high application potential in ion exchange, gas separation and storage, catalysis, fluorescence sensing, and drug delivery.
The quantitative detection of target components can be achieved by using changes in fluorescence intensity after the interaction between MOFs with fluorescence emission properties and guest molecules. For MOFs with a single ligand luminescence, the quantitative method is vulnerable to external interference, and the accuracy of the results is affected. The properties of metal ions and organic ligands determine the fluorescence properties of MOFs, which is the focus of research in this field. The trivalent lanthanide ion (Ln³⁺) has a 4f electron layer, which is incompletely filled, and exhibits unique fluorescence properties. Besides, it is prone to coordination with oxygen and nitrogen atoms. It can form high-coordination complexes with a particular topological structure by coordinating with organic ligands. Lanthanide metal-organic frameworks (Ln-MOFs) formed by Ln³⁺ and organic ligands are widely used as ratio fluorescent probes because of their ordered structure and high specific surface area, as well as the combined fluorescence properties of organic ligands and lanthanides. Ln-MOFs that respond to different components can be deve-loped by selecting different organic ligands and lanthanides.
This paper offers a retrospection of the research efforts with respect to the progress of Ln-MOFs in fluorescence detection and temperature sensing of anions, cations and small molecules. This paper also provides analysis of the detection results, detection mechanism and influencing factors. Moreover, we summarize the design concept of Ln-MOFs as fluorescent probes. Finally, we pay attention to the problems existing in the research on Ln-MOFs and focus on the prospect of its future development.

Fiber-reinforced cement-based composites, employing the cement paste, mortar or concrete as the base material and adulterated by various types of fibers, such as steel fiber, polyvinyl alcohol fiber, carbon fiber etc., to improve mechanical properties and durability of the base material, is a new type of cement-based composites. Based on the fiber-reinforced matrix theory, when fibers are uniformly distributed and their orientation is parallel to the direction of the matrix, they can effectively restrain the micro-fracture caused by the low tensile stress in cement-based composites and transfer the stress between the micro-fracture to prevent its further development at a micro level, while they can significantly improve the tensile and bending strength as well as ductility of cement-based composites at a macro level. However, the factors, such as types, the aspect ratio and dosages of fibers as well as the construction technology, affect the fiber orientation distribution in the matrix, severely weakening the fiber bridging action between the micro-fracture and increasing the fiber content, which not only adversely influences the tensile and bending strength as well as ductility-enhancing effect of cement-based composites, but also increases their production cost and greatly restricts their application.
Based on a large amount of recent research on the relationship between fiber orientation distribution and mechanical properties of cement-based composites by domestic and foreign scholars, this paper systematically summarizes the influence of orientation and spatial distribution for fibers on mechanical properties of cement-based composites, and summarizes the main factors affecting fiber orientation distribution. At the same time, various detection methods for evaluating fiber orientation distribution in matrix are introduced, and the advantages and disadvantages of different detection methods are analyzed. Finally, the development status of prediction models for fiber orientation distribution is discussed. This paper can provide reference for controlling the orientation distribution of fiber in cement-based composites, improving the tensile and bending strength as well as ductility of structures and reducing the production cost of fiber-reinforced cement-based composites.

The high-nickel ternary layered cathode materials have gradually become the main development direction of new commercial cathode materials for lithium-ion battery (LIB) due to their ultra-high energy density (250 W·h/kg) and theoretical specific capacity (200 mA·h/g) as well as low cost (50 yuan/kg). However, they often suffer structural problems such as high residual alkali,Ni²⁺/Li⁺ cation mixing, oxygen defects, particle cracking and phase transformation during the process of charging and discharging, which are prone to reduce the thermal stability and electrochemical performance. Starting with a brief introduction of the status quo of global commercial cathode materials for LIB and on the basis of a summary of the mechanisms behind capacity failure and structural degradation of high nickel ternary layered cathode materials, this review put emphasis on the pertinent improvement strategies including surface coating and bulk doping in recent three years. It ends with a prospective discussion on the future development trends such as single crystal system, low cobalt or no cobalt, electrolyte additives and safety performances, as well as the industrial commercialization.

Aerogel is a nano-scale porous solid material, which has the advantages of high specific surface area, extremely high porosity, extremely low density and extremely low thermal conductivity, but also has the problems of high brittleness and poor flexibility. In recent years, flexible aero-gels with prominent compression-resilience properties and flexural resistance have overcome the shortcomings of poor flexibility of traditional aerogels, and thus receive extensive attentions. This review firstly summarizes the types of flexible aerogels according to the components, including silicon oxide-based flexible aerogel, carbon-based flexible aerogel, biomass-based flexible aerogel and fibrous-based aerogel. Then, the related traditional preparation methods, such as sol-gel, aging, drying and so on, and also the differences in properties produced by different preparation processes have been systematically summarized. Furthermore, the applications of flexible aerogels in different fields such as environmental protection, optics, biomedicine, flexible electronic sensors and aerospace have been introduced. Finally, the development of flexible aerogels has been summarized and prospected.

High-energy ball milling technology with large-scale production potential has attracted great interest of researchers since its birth. However, the monolithic mechanical energy acts as input in the conventional ball milling process, which has some problems such as low efficiency, high energy consumption and powder contamination. In order to solve the above problems, it is of great significance to introduce external energy fields into ball milling process. In comparison with the conventional ball milling, external field-assisted ball milling has two advantages: (ⅰ) the milling time is significantly shortened; (ⅱ) special compounds can be synthesized.
At present, the commonly used external energy fields including ultrasonic, magnetic, temperature, electric and plasma were introduced into ball milling. Among them, plasma milling technology has been developed by introducing large area of dielectric barrier discharge plasma into milling process, which achieved the improvement of milling efficiency, milling capacity and process controllability. Many material systems have been involved in the application of plasma milling technology. However, due to the complexity and non-thermal equilibrium characteristics of cold plasma, the influence of plasma and coupling of plasma and mechanical force on the alloying characteristics and reaction mechanism of materials is still the key research content. In recent years, researchers have made great progress in fabricating different material systems through plasma milling.
The basic principle and characteristics of plasma milling and its applications in the preparation of various materials have been briefly introduced, and the special structure, excellent performance and corresponding formation mechanism of materials prepared by plasma milling are described. In view of the current research progress, the development prospects and challenges of plasma milling technology are also summarized, aiming to provide a reference for fabricating the high-performance materials by plasma milling.

The water and salt erosion of asphalt pavement is one of the main reasons for its performance deterioration and service life attenuation. In order to study the erosion damage law of water and salt in asphalt mixture, taking asphalt mortar and asphalt mortar-aggregate interface as the research objects, this work studied the influence of the physical and chemical properties of filler on the rheological properties and permeability of asphalt mortar and analyzed the attenuation law of interface strength of asphalt mortar-aggregate under different erosion conditions (static immersion and pressure immersion). It is found that the type of filler has little effect on the complex modulus of asphalt mortar, but its pore state and specific surface area have significant effects on the phase angle and permeability of asphalt mortar. Compared with ordinary immersion, salt solution erosion can significantly promote the strength attenuation of asphalt mortar-aggregate interface, and its attenuation rate is comprehensively affected by the physical (pore volume, specific surface area, micro morphology) and chemical (mineral composition, chemical composition) cha-racteristics of aggregate and filler. The effect of water pressure will accelerate the attenuation of asphalt mortar-aggregate interface strength, indicating that the dynamic water pressure generated by driving load will promote the water damage process of asphalt pavement.

Organic sulfur is the key and difficult point in the purification of coke oven gas, natural gas, yellow phosphorus tail gas, synthetic ammonia and other gases, among which COS and CS₂ account for the main part. Catalytic hydrolysis is considered to be one of the most effective ways to purify organic sulfur in industrial gases, which is a low-cost and high-efficiency purification technology. COS and CS₂ can be converted to H₂S by catalytic hydrolysis at lower temperature, and H₂S can be then removed efficiently. There are two major advantages for refined desulfurization by catalytic hydrolysis: (i) high conversion rate, low reaction temperature, and no hydrogen source consumption; (ii) mature purification process of the hydrolysate H₂S, which can be used for the recovery of sulfur resources.
Catalytic hydrolysis has been well studied and applied in industry, but the oxidation reaction in the hydrolysis process is an important reason for the reduction of the efficiency and life of the hydrolysis catalyst. Therefore, the development of cheap and efficient hydrolysis catalysts has become a research hotspot in this field. Moreover, high selectivity of H₂S is a core indicator of organic sulfur hydrolysis catalysis.
The hydrolysis catalysts prepared with γ-Al₂O₃ and activated carbon as support are the catalysts with a better application effect at present. Besides, the application of γ-Al₂O₃ is the earliest and most extensive, but its poor antioxidant capacity and catalyst poisoning characteristics make it limited in the application process. Supports such as TiO₂ and ZrO₂ have been followed with interest in recent years, and the addition of different active components provides the possibility to break through the low selectivity of H₂S and anti-toxicity. In addition, the study on the mechanism of organic sulfur hydrolysis also provides a theoretical basis for the development of hydrolytic catalysts. On this basis, the activity and life of organic sulfur hydrolysis catalysts can be improved by adjusting the reaction path and improving influencing factors in the hydrolysis process.
This review introduces the research and application of the main supports and active components on COS and CS₂ catalytic hydrolysis. The hydrolysis mechanism of organic sulfur and hydrolysis catalyst deactivation reason has also been summarized, and the problems faced and future prospect of the catalytic hydrolysis method are analyzed. It is hoped that this paper can provide reference for the design of new high efficiency hydrolytic catalytic materials.

Recently, China and USA and other countries have achieved tremendous process in the aviation and aerospace industry.The manned spacecrafts, such as ‘Shenzhou ⅩⅢ' of China and ‘Dragon spacecraft' of Space X and ‘New Shepard' of Blue Origin of the USA, have been successfully launched, signifying that the human exploration of space is entering a new era.Obviously, these achievements are closely related the rapid development of the industry of materials with high performance.‘One generation of materials, one generation of technology and one generation of equipment' as the famous aphorism points out, the understanding, researching, development and usage of materials as the basic, primitive and most essential driving force in the history of human society play a crucial role in promoting the development of the defense of the whole country.Aerogel, a kind of lightweight porous material, has attracted more and more attention in the aviation and aerospace industry because of its high efficiency thermal insulation property.In this paper, the research progress of oxides aerogels (such as SiO₂, Al₂O₃ and ZrO₂ aerogels) and non-oxide aerogels (such as carbon, carbide and boride aerogels) in the aviation and aerospace industry is reviewed.The molecular structure design, preparation methods, thermodynamic properties and other aspects of aerogel materials are mainly discussed in detail in order to provide beneficial advice and suggestion concerning related basic scientific research in this aspect.

Carbon material is one of the most important electrode materials of electrochemical capacitor; however, it is always a challenge for carbon materials to be wetted by aqueous electrolyte with polarity, due to the intrinsic non-polarity of carbon materials surface. Herein, polyethylene glycol (PEG) molecular brushes with excellent hydrophilicity were grafted on carbon microspheres (C_sa) surface through polymer grafting to improve the wettability of the C_sa as electrode active materials toward aqueous electrolyte. The dispersibility test of electrode materials in 6 mol/L KOH electrolyte and static water contact angels showed that the PEG molecular brushes modified C_sa (P-C_sa) was better to be wetted by aqueous electrolyte than the unmodified C_sa. Electrochemical tests, such as cyclic voltammograms, galvanostatic charge-discharge, electrochemical impedance spectroscopy, demonstrated that the specific capacity of P-C_sa electrode material was nearly 60% higher than that of unmodified C_sa electrode material at current density of 0.625 A/g, and the P-C_sa electrode material also exhibited excellent rate performance, low intrinsic impedance (0.94 Ω) and high cycle stability (73.29% of the initial specific capacity after 10 000 cycles at current density of 1.25 A/g). It is worth pointing out that the modification of PEG molecular brushes for C_sa electrode material does not introduce faradic pseudocapacitance, which mainly improves the wettability of electrode materials surface toward aqueous electrolyte.

Additive manufacturing, also known as 3D printing, is a digital manufacturing technology based on discrete stacking principle. Due to its high flexibility and rapidity, additive manufacturing has received widespread attention. It can reduce the production cost, shorten the manufacturing cycle, and quickly respond to the personalized needs of customers for molded products with additive manufacturing technology to manufacture mold or die.
Rapid tooling based on additive manufacturing(AM) is also known as rapid tooling technology. According to whether the part based on additive manufacturing is directly used as a mold or die, rapid tooling is divided into indirect rapid tooling and direct rapid tooling. According to the hardness of the mold or die material, rapid tooling is divided into hard tooling and soft tooling. Indirect rapid tooling has developed from indirect soft tooling such as silicone tooling, to indirect hard tooling. Due to the complex process and low precision of indirect rapid tooling and short life of soft tooling, with the development of additive manufacturing and material, more and more attention has been paid to direct rapid tooling in recent years.
This article mainly reviews the development history, process principle and typical process of rapid tooling based on additive manufacturing, and compares and analyzes these processes of rapid tooling. Meanwhile, it summarizes the basic principles, typical processes and characteristics of rapid tooling based on additive-subtractive hybrid manufacturing, and new materials used in rapid tooling. For rapid tooling, there are many drawbacks such as low precision, poor surface quality, internal defects of the mold or die, anisotropy of mechanical properties, limited size of mold or die and high cost. Therefore, rapid tooling will trend to high precision, high surface quality, high mechanical properties and low cost. The additive and subtractive hybrid manufacturing will be applied more than additive manufacturing. At the same time, the defect detection and control in the rapid tooling will become a research hotspot.

The Bioeconomy has attracted extensive attention from industry and commerce, academia and government owing to the fast-paced transformation of food, environment, medicine, energy and other industries. Thus, it is of vital significance to effectively analyze, develop, and utilize biological resources such as natural macromolecules. Natural starch is favored due to its wide source, low price, non-toxicity, non-immunogenicity, biodegradation, regeneration, excellent adhesion and biocompatibility. However, starch films exhibit poor water resistance and strength. In this respect, the functional properties of the starch films can be improved by blending them with other materials owing to the chemical bonding and intermolecular forces. This review introduces the preparation of starch composite films with cellulose, chitosan, protein, aliphatic polyester, polyvinyl alcohol, polyolefin plastics, nano-oxide, clay, zirconium phosphate (phosphonate) and fiber by solvent casting, compression, extrusion and injection blow molding. And then it summarizes the water resistance, mechanical properties, biodegradability, water vapor permeability, thermal stability, compatibility and bacterial resistance of composite films, and discusses the applications of composite films in the food packaging, environment and biomedicine fields. This review prospects that the supercritical fluid and ultrasonic activation impart the modified starch with improved film properties, and the research direction is at excellent biocompatibility intercalation material in future.