Study On Photoelectric Properties Of Ferroelectric Film Material

As an important class of functional materials,ferroelectric perovskites.Bismuth ferrite based compounds have attracted a lot of attention because of their special structures,properties and wide application prospects.but its large leakage current limits its application to a large extent.possess large doping tolerance from the structural characteristics and chemical simplicity,which makes the symmetry,carrier concentration,band-gap,etc.be.The band gap of BiFeO₃ is much smaller than other ferroelectric materials.In the area of ferroelectric photovoltaics,the great attraction of ferroelectrics locates on the discovery and application of ferroelectric photovoltaic effect.In consideration of application in the application of solar cells,we have prepared BiFeO₃ and their derivatives thin films by Sol-gel method.We have prepared Bi_1-xLa_xFeO₃?x=0.00,0.05,0.1?,Bi_1-xNd_xFeO₃?x=0.00,0.03,0.07,0.10?films and BiFe_1-xCr_xO₃?x=0.00,0.02,0.04,0.06,0.08,0.10?.And through the multi-characterization test method,its influence on the barium ferrite film was analyzed from the aspects of microstructure,microstructure,optics and electricity.The main work results are as follows:The La-doped BFO film was successfully prepared.With the increase of La doping amount,the oxygen vacancies of the film were effectively suppressed,the oxygen vacancy concentration was reduced,the residual polarization value was greatly enhanced,and the leakage current was decreased.The absorption rate increases and the optical band gap decreasesThe Nd-doped BFO film was successfully prepared.With the increase of Nd doping amount,the residual polarization value of the film increased,the coercive field increased,the oxygen vacancies of the film were effectively suppressed,and the oxygen vacancy concentration decreased;indicating Nd³⁺The introduction can compensate and suppress the volatilization of Bi³⁺,thereby reducing the oxygen vacancy concentration and reducing the leakage current.From the absorption spectrum,the bandwidth tends to become smaller.When the content of Nd is x=0.07the optical band gap value reaches a minimum of 2.11 eV.The Cr-doped BFO film was successfully prepared.With the increase of Cr doping amount,the residual polarization value of the film increased,the coercive field increased,the oxygen vacancy of the film was effectively suppressed,the oxygen vacancy concentration was reduced,and the leakage was reduced.Current density;It can be concluded from the absorption spectrum that the doping of Cr causes the absorption range of the BiFeO₃ film to expand red,indicating that the doping of Cr can reduce the optical band gap of the BiFeO₃ film.