Improved photovoltaic properties of nominal composition CH3NH3Pb0.99Zn0.01I3 carbon-based perovskite solar cells.

Herein, the low-cost and eco-friendly zinc cation (Zn2+) is used to replace part of the lead cation (Pb2+) in methylammonium lead iodide (CH3NH3PbI3). The modified perovskite material, CH3NH3PbxZn1-xI3, is then obtained and successfully applied in the construction of hole-conductor-free perovskite solar cells (PSCs) based on carbon counter electrodes. The obtained PSCs with 1 mol% Zn doping dramatically facilitate the formation of dense, high surface coverage perovskite films with large grain size and superior crystallinity. Especially, the power conversion efficiency is up to 15.37%, which is a 14.8% increase, compared to the pristine PSCs. This work finds a superior way to further research lead-reduced PSCs.