Effect Of TiO₂ Compact Layer On The Properties Of Organic-inorganic Hybrid Perovskite Solar Cells By Magnetron Sputtering

The photoelectric conversion efficiency of the perovskite solar cell has exceeded 20%,reaching to 22.1%.The gap of the photoelectric conversion efficiency between the perovskite solar cell and the traditional silicon based solar cell is rapidly decreasing.In the continuous study of perovskite solar cell,the researchers find that structure and properties have a significant impact on the photovoltaic performance.The compact layer mainly absorbe electrons generated in perovskite layer and separate the electron hole.Therefore,the high quality of titanium dioxide compact layer helps to reduce the recombination of carriers and avoid short circuit.Considering the significant effect of TiO2 compact layer,Preparation method of TiO2 compact layer has attracted a lot of attentions.The film will change with the different TiO2 compact layer preparation process,which will not only affect the surface morphology of the mesoporous TiO2 layer,but also indirectly change the perovskite layer.Fanally it affects the performance of perovskite solar cell.The main research contents and conclusions of this paper are as follows:TiO2 compact films with different thickness were deposited by DC magnetron sputtering,and the effect of the thickness of TiO2 compact layer on the properties of organic inorganic hybrid perovskite solar cells was studied.The TiO2 compact layer morphology,properties and the influence in organic-inorganic hybrid perovskite type solar cell was analyzed by field emission scanning electron microscopy,X-ray diffraction,step profiler,UV-VIS spectrophotometer,electrochemical workstation and the solar simulator.The optimum thickness and the best deposition time of TiO2 compact layer were obtained by analyzing the efficiency of the cell device.In DC magnetron sputtering,94 nm was the best thickness of TiO2 compact layer,the corresponding cell conversion efficiency up to 9.73%,the short-circuit current of 27.15 mA/cm2,open circuit voltage of 895mV,the fill factor of 40.02%.In RF magnetron sputtering,89 nm was the best thickness of TiO2 compact layer while the highest cell conversion efficiency was 8.52%,the corresponding short circuit current was 18.79 mA/cm2,the open circuit voltage was 945 mV,the filling factor was 49.18%.It shown that in this thickness,the electron in the interface between the TiO2 compact layer and the FTO conductive glass had high electron transfer rate,as well as in the TiO2 compact layerTiO2 compact layer was tentatively prepared in the best thickness and the optimum deposition time which obtained by DC magnetron sputtering.And it was directly used as the compact layer of perovskite solar cells without high temperature annealing.The conditions of low temperature deposition of crystallized TiO2 compact layers were explored.TiO2 compact layer was prepared by spin-coating solution method in low temperature.Crystallized TiO2 compact layer was obtained by thermal crystallization treatment and used in the perovskite solar cell to achieve the purpose of flexible devices.In this experiment,a certain efficiency of the cell device was prepared by DC magnetron sputtering and thermal crystallization treatment in low temperature.It indirectly indicated that the TiO2 compact layer prepared in low temperature had a certain crystal structure.