Graphdiyne-Based Bulk Heterojunction for Efficient and Moisture-Stable Planar Perovskite Solar Cells

Graphdiyne (GDY) is introduced into the FA(0.85)MA(0.15)Pb(I0.85Br0.15)(3) perovskite film to construct a perovskite/graphdiyne (PVSK/GDY) bulk heterojunction for planar perovskite solar cells (PSCs). This PVSK/GDY bulk heterojunction is suggested to provide an extra channel to favor exciton separation and facilitate the photogenerated electron extraction ability. The electron transportation ability has been improved for higher J(sc), and the introduction of GDY can passivate grain boundaries and interfaces to effectively suppress photogenerated carrier recombination, leading to relatively higher fill factor. Up to 20.54% power conversion efficiency is achieved. In addition, the ability of this perovskite film with PVSK/GDY bulk heterojunctions to function in humid conditions is also improved, leading to good stability of PSCs toward moisture. This work provides a new way to fabricate highly efficient, stable PSCs by constructing bulk heterojunctions simultaneously for accelerating the exciton separation and photogenerated electron transportation and improving the device stability.