Planar heterojunction perovskite/PC 71 BM solar cells with enhanced open-circuit voltage via a (2/1)-step spin-coating process

A two-step spin-coating process was used to synthesize perovskite films at ambient conditions. Combining a PEDOT:PSS hole-transport layer and a PC 71 BM acceptor, the device achieves a power conversion efficiency of 16.31% with a remarkably high V oc of 1.05 V and FF of 0.78.