High efficiency CH3NH3PbI3:CdS perovskite solar cells with CuInS2 as the hole transporting layer
Chong Chen∗, Yong Zhai,Fumin Li,Furui Tan, Gentian Yue, Weifeng Zhang, Mingtai Wang
The CH3NH3PbI3:CdS composite films are prepared by a newly developed precursor blending solution method, which are further used to abricate CH3NH3PbI3:CdS perovskite solar cells. Our experimental results demonstrate that the introduced CdS effectively improves the light absorption property of the ITO/CuInS2/Al2O3/CH3NH3PbI3:CdS film stack and decreases the charge recombination in the prepared solar cells due to the formation of CH3NH3PbI3/CdS bulk heterojunction. Furthermore, the formed CdS/CuInS2 heterojunction also contributes to the enhanced efficiency. As a consequence, the CH3NH3PbI3/CdS bulk heterojunction perovskite solar cells exhibit a maximum power conversion efficiency of (16.5 ± 0.2)%, which is 1.35 times the best efficiency of 12.2% of previously reported CdS/CH3NH3PbI3 bilayer solar cell. In addition, this efficiency is a 59% improvement compared with the efficiency of (10.4 ± 0.2)% for the ITO/CuInS2/Al2O3/ CH3NH3PbI3/PC60BM/Ag cell without CdS.