Study on the performance of urea doped CH3NH3PbI3 thin film and its perovskite solar cells
A perovskite solar cell absorbing layer CH3NH3PbI3 thin film was prepared using a one-step spin coating method.Urea was added during the preparation of the absorbing layer,and the effect of urea doping on the phase structure and microstructure of CH3NH3PbI3 thin films was studied,as well as on the photoelectric performance of perovskite solar cells assembled.The samples were characterized by XRD,SEM,UV-Vis,PL and J-V curves.The results showed that the addition of appropriate amount of urea increased the crystallinity of CH3NH3PbI3 film,improved its orientation and coverage,and reduced the number of pores and cracks.When the doping amount of urea was 10 mol％,the grain size of the film was the most uniform and the crystallization performance was the best.All CH3NH3PbI3 thin films have absorption edges around 780 nm and a bandgap width of 1.5 eV.The addition of appropriate amount of urea improved the absorbance and emission peak intensi-ty of CH3NH3PbI3 film.With the increase of urea doping amount,the absorbance and emission peak intensity of CH3NH3PbI3 film first increased and then decreased.When the doping amount of urea was 10 mol％,the ab-sorption property of CH3NH3PbI3film was the best,and the emission peak intensity was the highest.30 perovs-kite solar cells were assembled using CH3NH3PbI3 thin films with different levels of urea doping,and the J-V curves were tested.When the doping amount of urea was 10 mol％,the cell had the best photoelectric perform-ance,and its solar-cell efficiency reached the maximum of 20.61％.The above analysis shows that the optimal doping amount of urea is 10 mol％.
万方数据
