Xu Yuzhuan, Zhu Lifeng, Shi Jiangjian, Lv Songtao, Xu Xin, Xiao Junyan, Dong Juan, Wu Huijue, Luo Yanhong, Li Dongmei, Meng Qingbo
Key Laboratory for Renewable Energy, Chinese Academy of Sciences, Beijing Key Laboratory for New Energy Materials and Devices, Institute of Physics, Chinese Academy of Sciences , Zhongguancun South Third Street 8, Haidian District, Beijing 100190, China.
ACS Appl Mater Interfaces. 2015 Feb 4;7(4):2242-8. doi: 10.1021/am5057807. Epub 2015 Jan 23.
A morphology-controlled CH3NH3PbI3-xClx film is synthesized via two-step solution deposition by spin-coating a mixture solution of CH3NH3Cl and CH3NH3I onto the TiO2/PbI2 film for the first time. It is revealed that the existence of CH3NH3Cl is supposed to result in a preferential growth along the [110] direction of perovskite, which can improve both the crystallinity and surface coverage of perovskite and reduce the pinholes. Furthermore, the formation process of CH3NH3PbI3-xClx perovskite is explored, in which intermediates containing chlorine are suggested to exist. 13.12% of power conversion efficiency has been achieved for the mesoscopic cell, higher than 12.08% of power conversion efficiency of the devices fabricated without CH3NH3Cl via the same process. The improvement mainly lies in the increasing open-circuit photovoltage which is ascribed to the reduction of reverse saturation current density.
首次通过两步溶液沉积法，将CH3NH3Cl和CH3NH3I的混合溶液旋涂在TiO2/PbI2薄膜上，合成了形貌可控的CH3NH3PbI3-xClx薄膜。结果表明，CH3NH3Cl的存在会导致钙钛矿沿[110]方向优先生长，这可以提高钙钛矿的结晶度和表面覆盖率，并减少针孔。此外，还探索了CH3NH3PbI3-xClx钙钛矿的形成过程，其中表明存在含氯中间体。介观电池的功率转换效率达到了13.12%，高于通过相同工艺制备的不含CH3NH3Cl的器件的12.08%的功率转换效率。这种提高主要在于开路光电压的增加，这归因于反向饱和电流密度的降低。
