The Preparation And Ferroelectric Photovoltaic Properties Of Bismuth-based Oxide Composite Films

Since the beginning of the new century,the multiferroic materials has been rapidly developed because it has excellent application prospects in the new information storage devices,sensors and photoelectric materials and other fields.Bi-based oxide BiFeO₃,as one of representatives of multiferroic materials,which has abnormal photovoltaic effect and theoretically there is a high photoelectric conversion efficiency,these characteristics make it a hot research topic in the material industry.However,due to the shortcomings of BiFeO₃ material such as poor filming quality,large leakage current,and low photoelectric conversion efficiency,its ferroelectric properties and photovoltaic properties have yet to be improved.In this paper,BiFeO₃/BiVO₄ composite films were successfully prepared by using the method of forming composite thin films,their microstructures,ferroelectric properties and photovoltaic properties were characterized.The results show that BiFeO₃/BiVO₄ composite films formed a polycrystalline thin film with good crystallinity,and had good leakage characteristics and dielectric properties.At the same time,the optical properties were greatly improved,and the photovoltaic effect could be obtained in a wide range of wavelengths,and the photovoltaic spectral response of the BiFeO₃/BiVO₄ composite films had a obvious redshift towards the visible region.In this paper,the BiFeO₃ films with LaNiO₃ as the bottom electrode were prepared on Si?100?substrates successfully by the method of introducing LaNiO₃ buffer layer,and properties of the BiFeO₃ films was analyzed and discussed.The results show that the oxide LaNiO₃ is used as the bottom electrode,which realized the preferential growth of the ferroelectric films and greatly reduced the leakage current,and the ferroelectric properties of the ferroelectric films have been improved.