Abstract: With the rapid development of science and technology, multiferroic materials have become a research focus in the fields of sensors, microwave devices, data storage, spintronics, solar cells and so forth, exhibiting considerable application potential in intelligent materials and devices. The discovery of BiFeO3 and its derivatives, like Bi1-xAxFeO3 (A=La, Nd, Sm) and BiFexB1-xO3 (B=Ni, Mn, Co), has greatly accele-rated the advance of the multiferroic materials. This kind of material belongs to the single-phase perovskite type multiferroic materials, showing its superiority in integrated effects of ferroelectric, piezoelectric, dielectric, electrooptic, ferromagnetic, photovoltaic, magnetoelectric coupling and photocatalytic properties over room temperature. As a single phase multiferroic material, BiFeO3 features higher Curie temperature and Neal temperature, smaller optical band gap and better chemical stability compared with similar ferroelectric material. However, in the process of preparing BiFeO3, partial Fe3+ is converted to Fe2+, and bismuth is likely to volatilize because of its low melting point, producing a large number of oxygen vacancies and resulting in large leakage current. It is very difficult to have high residual polarization samples. Besides, weak magnetic properties of the BFO films at room temperature greatly limit its practical application. Over the years, scholars at home and abroad have devoted themselves to improving the preparation conditions and parameters, developing more advanced preparation methods, selecting more suitable substrate materials, preparing multilayer composite films and conducting ion doping et al. Among all the improvement approaches, ion doping plays the most prominent role to reduce leakage current, improve ferroelectricity and room temperature magnetism. Researchers over the world have successively prepared doped and composite BiFeO3 materials with superior properties to pure BiFeO3. Doping multiple elements at different positions rather than doping single element exert more favorable effect on improving the performance of BiFeO3materials. The residual polarization of Bi0.88Sr0.03Gd0.09Fe0.94Mn0.04Co0.02O3 films with mixed doped ions prepared by sol-gel method has been raised to 108 μC/cm2, which is significantly higher than that of materials singly doped by La, Mn, Zn and other elements (69.47 μC/cm2). Meanwhile, the magnetization of the doped BiFeO3 film is three to four times higher than that of the pure BiFeO3 film. This may be derived from the inhibition of Bi3+ volatilization and Fe3+ reduction by doping elements, which contribute to reducing the oxygen vacancy and defect concentration, controlling the leakage current and raising the dielectric constant, and further improving the ferroelectric properties of the BiFeO3 film. In addition, doping elements also lead to the structural distortion and break the spiral magnetic structure of the material, thus producing strong magnetic properties at room temperature. Firstly, the structure of BiFeO3 materials and the types of doped elements in its modification are briefly described in this article. Secondly, the effects of A, B and AB co-doped ions on improving weak magnetic properties of BiFeO3 thin films and improving ferroelectric properties by redu-cing leakage current are discussed, and the reasons for the influences are further summarized. Finally, the research work to be carried out is proposed.
1 Azizi Z S, Tehranchi M M, Hamidi S M, et al. Physica Status Solidi,2017,214(2),1600505. 2 Jochum J K, Lorenz M, Gunnlaugsson H P, et al. Nanoscale,2018,10(12),5574. 3 Guo B L, Deng H M, Zhai X Z, et al. Materials Letters,2017,186,198. 4 Mori T J A, Mouls C L, Morgado F F, et al. Journal of Applied Physics,2017,122(12),124102. 5 Hasan M, Islam M F, Mahbub R, et al. Materials Research Bulletin,2016,73,179. 6 Wu H, Xue P, Lu Y, et al. Journal of Alloys and Compounds,2018,731,471. 7 Gomez-Iriarte G A, Labre C, De Oliveira L A S, et al. Journal of Magnetism and Magnetic Materials,2018,460,83. 8 Fiebig M, Lottermoser T, Meier D, et al. Nature Reviews Materials,2016,1(8),1. 9 Trassin M. Journal of Physics: Condensed Matter,2016,28(3),033001. 10 Fiebig M, Lottermoser T, Meier D, et al. Nature Reviews Materials,2016,1(8),16046. 11 Nicola A S. MRS Bulletin,2017,42(5),385. 12 Sharma S, Saravanan P, Pandey O P, et al. Journal of Materials Science: Materials in Electronics,2016,27(6),5909. 13 Vanga P R, Mangalaraja R V, Ashok M. Journal of Materials Science: Materials in Electronics,2016,27(6),5699. 14 Deng X L, Wang W, Gao R L, et al. Journal of Materials Science: Materials in Electronics,2018,29(8),6870. 15 Ling F, Liu L M, Chen X B, et al. Bulletin of the Chinese Ceramic Society,2015,34,262. 16 Jalaja M A, Soma Dutta. Advanced Materials Letters,2015,6(7),568. 17 Kuila S, Tiwary S, Sahoo M R, et al. Journal of Alloys and Compounds,2017,709,158. 18 Zhang Y L, Qi J, Wang Y H, et al. Ceramics International,2018,44(6),6054. 19 Huang Y Ch, Liou Y D, Liu H J, et al. APL Materials,2017,5(8),086112. 20 Yu L, Deng H M, Zhou W L, et al. Materials Letters,2016,170,85. 21 Wang C J, Zhang F Q, Guo X D, et al. Rare Metal Materials and Engineering,2015,44(1),13. 22 Wang T T, Deng H M, Meng X K, et al. Ceramic International,2017,43,8792. 23 Yan J, Hu G D, Jiang X M. Journal of Materials Science: Materials in Electronics,2017,28,10400. 24 Agbelele A, Sando D, Toulouse C, et al. Advanced Materials,2017,29(9),16023270. 25 Lam S M, Sin J C, Mohamed A R. Materials Research Bulletin,2017,90,15. 26 Xie H, Tan J B, Gu Q B. Journal of Hubei University of Education,2017,34(8),8(in Chinese). 谢浩,谭敬铂,顾期斌.湖北第二师范学院学报,2017,34(8),8. 27 Cui S M, Xu Y F, Zhou T, et al. Journal of Huzhou Teachers College,2016,38(10),14(in Chinese). 崔晓明,徐燕飞,周挺,等.湖州师范学院学报,2016,38(10),14. 28 Anju, Ashish A, Praveen A, et al. Ceramic International,2017,43,7408. 29 Pulikkathodi A K, Suresh V, Yang S M, et al. In: Conference Record of the 2013 IEEE International Conference of Electron Devices and Solid-state Circuits. Hong Kong, China,2013,pp.1. 30 Laughlin R P, Currie D A, Contreras-Guererro R, et al. Journal of Applied Physics,2013,113(17),9191. 31 Heron J T, Schlom D G, Ramesh R, et al. Applied Physics Reviews,2014,1(2),3031. 32 Zi Y B. Study on the preparation and properties of BiFeO3 thin film and devices. Master’s Thesis, University of Science and Technology of China, China,2009(in Chinese). 訾玉宝.BiFeO3薄膜及器件的制备与性能研究.硕士学位论文,中国科学技术大学,2009. 33 Li J F, Wang J L, Wuttig M, et al. Applied Physics Letters,2004,84(25),5261. 34 Gupta S, Tomar M, James A R, et al. Journal of Materials Science,2014,49(15),5355. 35 Yan F, Zhu T J, Lai M O, et al. Scripta Materialia,2010,63(7),780. 36 Sun W, Li J F, Yu Q, et al. Journal of Materials Chemistry C,2015,3(9),2115. 37 Xing W, Ma Y, Ma Z, et al. Smart Materials and Structures,2014,23(8),085030. 38 Yan F, Lai M O, Lu L, et al. Journal of Physical Chemistry C,2010,114(15),6994. 39 Barman R, Kaur D. Vacuum,2017,146,221. 40 Yang S, Zhang F, Xie X, et al. Journal of Alloys and Compounds,2018,734,243. 41 Dong G, Tan G, Liu W, et al. Ceramics International,2014,40(1),1919. 42 Kawae T, Tsuda H, Morimoto A. Applied Physics Express,2008,1,051601. 43 Yan X, Tan G, Liu W, et al. Ceramics International,2015,41(2),3202. 44 Yun Q, Xing W, Chen J, et al. Thin Solid Films,2015,584,103. 45 Chai Z J, Tan G Q, Yue Z W, et al. Journal of Alloys & Compounds,2018,746(25),677. 46 Zhang J. Structure and magnetic properties in La, Er doped BiFeO3 thin films. Master’s Thesis, Jilin Normal University, China,2014(in Chinese). 张静.Er,La掺杂对BiFeO3薄膜的结构和磁性的影响.硕士学位论文,吉林师范大学,2014. 47 Lee Y H, Wu J M, Lai C H. Applied Physics Letters,2006,88(4),0429031. 48 Lazenka V V, Ravinski A F, Makoed I I, et al. Applied Physics Reviews,2012,111(12),1239161. 49 Anthonyraj C, Muneeswaran M, Gokul Raj S, et al. Journal of Materials Science: Materials in Electronics,2015,26(1),49. 50 Zhai X Z, Deng H M, Yang P X, et al. Materials Letters,2015,158,266. 51 Cui J Y, Yang P X, Chu J H. Journal of Infrared and Millimeter Waves,2016,35(3),322(in Chinese). 崔金玉,杨平雄,褚君浩.红外与毫米波学报,2016,35(3),322. 52 Li M, Hu Z, Pei L, et al. Ferroelectrics,2010,410(1),3. 53 Fu C J, Huang Z X, Li J, et al. Materials Review B: Research Papers,2010,24(2),17(in Chinese). 付承菊,黄志雄,李杰,等.材料导报:研究篇,2010,24(2),17. 54 Gao F, Cai C, Wang Y, et al. Applied Physics,2006,99(9),0941051. 55 Yuan G L, Siu Wing Or, Chan H L W, et al. Applied Physics,2007,101(2),0241061. 56 Guo D Y, Li C, Wang C B, et al. Acta Physica Sinica,2010,59(8),5772(in Chinese). 郭冬云,李超,王传彬,等.物理学报,2010,59(8),5772. 57 Liu J, Deng H M, Zhai X Z, et al. Material Letters,2014,133(10),49. 58 Sharma Y, Martinez R, Agarwal R, et al. Applied Physics,2016,120(19),101. 59 Baetting P, Ederer C, Spaldin N A, et al. Physical Review B,2005,72(21),2141051. 60 Liu K T, Li J, Xu J B, et al. Journal of Materials Science: Materials in Electronics,2017,28(7),5609. 61 Wang T T, Deng H M, Cao H Y, et al. Materials Letters,2017,199,116. 62 Kuang D H, Tang P, Wu X H, et al. Journal of Alloys and Compounds,2016,8388(16),303501. 63 Du L Q, Deng S L, Xi H M, et al. Materials Review B: Research Papers,2016,30(11),43(in Chinese). 杜奕全,邓施列,冼慧敏,等.材料导报:研究篇,2016,30(11),43.