RESEARCH PAPER |
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Hydrothermal Synthesis of 1-D α-MoO3 Nanorods and Their Humidity Sensing Properties |
LI Jintao, WU Yuhui, LIU Zhuo, ZHAO Jing, WANG Shengli
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Experimental Practising & Teaching Center, Hebei GEO University, Shijiazhuang 050031 |
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Abstract 1-D α-MoO3 nanorods were synthesized under hydrothermal conditions by using (NH4)6Mo7O24·4H2O and HNO3 as raw materials. X-ray diffraction (XRD), scanning electron microscope (SEM) and transmission electron microscope (TEM) were used to characterize phase and morphology of the samples. The width of the α-MoO3 nanorod was about 200-300 nm, and the length was about 5-10 μm. 1-D α-MoO3 nanorods showed good humility sensing properties. The curve of impedance vs. relative humility (RH) changed near five orders of magnitude with good linearity, when RH varied from 11% to 95% at 100 Hz. The response and recovery time of the sensor were about 3 s and 35 s, respectively. The maximum hysteresis was only 4% RH at 100 Hz. In order to explain the conduction process of the sensor, corresponding equivalent circuits were established by complex impedance plots of the device at various humidity ranges. In low RH range, the conduction process was dominated mainly by conduction (charge carriers) and polarization (bounded electrons) of the grains of 1-D α-MoO3 nanorods, while in high RH range, by decomposition and polarization of the absorbed water.
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Published: 25 March 2017
Online: 2018-05-02
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1 Rubinger C P L, Martins C R, De Paoli M A, et al. Sulfonated polystyrene polymer humidity sensor: Synthesis and characterization [J]. Sens Actuators B,2007,123(1):42. 2 Li L Y, Dong Y F, Jiang W F, et al. High-performance capacitive humidity sensor based on silicon nanoporous pillar array [J]. Thin Solid Films,2008,517(2):948. 3 Fang Xiangyi, Wu Mingtang, Jiang Yun, et al. Manufacture and humidity sensitivity of porous SiO2 thick film humidity sensors [J]. Electron Compon Mater,1995,14(5):19(in Chinese). 方湘怡,武明堂,姜芸,等.多孔SiO2厚膜湿度传感器的制造及其湿敏特性[J].电子元件与材料,1995,14(5):19. 4 Yang Z, Zhang Z, Liu K, et al. Controllable assembly of SnO2 nanocubes onto TiO2 electrospun nanofibers toward humidity sen-sing applications [J]. J Mater Chem C,2015,3(26):6701. 5 Pascariu P, Airinei A, Olaru N, et al. Microstructure, electrical and humidity sensor properties of electrospun NiO-SnO2 nanofibers [J]. Sens Actuators B,2016,222:1024. 6 Wei G, Qin W, Zhang D, et al. Synthesis and field emission of MoO3 nanoflowers by a microwave hydrothermal route [J].J Alloys Compd,2009,481(1-2):417. 7 Sinaim H, Phuruangrat A, Thongtem S, et al. Synthesis and cha-racterization of heteronanostructured Ag nanoparticles/MoO3 nanobelts composites [J]. Mater Chem Phys,2012,132(2-3):358. 8 Li Y B, Bando Y, Golberg D, et al. Field emission from MoO3 nanobelts [J]. Appl Phys Lett,2002,81(26):5048. 9 Comini E, Yubao L, Brando Y, et al. Gas sensing properties of MoO3 nanorods to CO and CH3OH [J]. Chem Phys Lett,2005,407(4-6):368. 10 Bai S, Chen S, Chen L, et al. Ultrasonic synthesis of MoO3 nanorods and their gas sensing properties [J]. Sens Actuators B,2012,174(11):51. 11 Wang Q, Sun J, Wang Q, et al. Electrochemical performance of α-MoO3-In2O3 core-shell nanorods as anode materials forlithium-ion batteries [J]. J Mater Chem A,2015,3(9):5083. 12 Wang Q, Wang Q, Zhang D, et al. Core-shell α-Fe2O3@α-MoO3 nanorods as lithium-ion battery anodes with extremely high capacity and cyclability [J]. Chem Asian J,2014,11(9):3299. 13 Fang L, Shu Y, Wang A, et al. Green synthesis and characterization of anisotropic uniform single-crystal α-MoO3 nanostructures [J]. J Phys Chem C,2007,111(6):2401. 14 Jiang D, Wang Y, Wei W, et al. Xylene sensor based on α-MoO3 nanobelts with fast response and low operating temperature [J]. RSC Adv,2015,5(24):18655. 15 Li X L, Liu J F, Li Y D. Low-temperature synthesis of large-scale single-crystal molybdenum trioxide (MoO3) nanobelts [J]. Appl Phys Lett,2002,81(25):4832. 16 Chithambararaj A, Bose A C. Investigation on structural, thermal, optical and sensing properties of meta-stable hexagonal MoO3 nanocrystals of one dimensional structure [J]. Beilstein J Nanotechnol,2011,2(2):585. 17 Jittiarporn P, Sikong L, Kooptarnond K, et al. Effects of precipitation temperature on the photochromic properties of h-MoO3 [J]. Ceram Int,2014,40(8):13487. 18 Wang Wendi, Xu Huayun, Liu Jinhua, et al. Hydrothermal synthesis of MoO3 nanobelts and their electrochemical characterization [J]. J Funct Mater,2006,37(3):434(in Chinese). 王文帝,徐化云,刘金华,等.MoO3纳米纤维电极材料的水热合成和电化学表征[J].功能材料,2006,37(3):434. 19 Kuang Q, Lao C, et al. High-sensitivity humidity sensor based on a single SnO2 nanowire [J]. J Am Chem Soc,2007,129(19):6070. 20 Kolmakov A, Moskovits M. Chemical sensing and catalysis by one-dimensional metal-oxide nanostructures [J]. Annu Rev Mater Res,2004,35(34):151. 21 Holc J, Sluncko J, Hrovat M. Temperature characteristics of electrical properties of (Ba,Sr)TiO3 thick film humidity sensors [J]. Sens Actuators B,1995,26(1-3):99. 22 Wang J, Xu B K, Ruan S P, et al. Preparation and electrical properties of humidity sensing films of BaTiO3/polystrene sulfonic sodium [J]. Mater Chem Phys,2003,78(3):746. 23 Wang J, Su M Y, Qi J Q, et al. Sensitivity and complex impedance of nanometer zirconia thick film humidity sensors [J]. Sens Actuators B,2009,139(2):418.
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