Fast preparation of compact and stable perovskite films derived from PbCl2 and Pb(Ac)2·3H2O mixed-lead-halide precursors

In this work, lead chloride (PbCl 2 ) and lead acetate trihydrate (Pb(Ac) 2 ·3H 2 O) mixed precursors are introduced to prepare perovskite films. PbCl 2 has been reported to enhance crystallinity but long annealing time is required. Pb(Ac) 2 ·3H 2 O is used because it is cheap and easy to get, and lead acetate offers fast crystallization process , meanwhile the trihydrate might improve the film stability. With an optimal blending ratio of the two precursors (1:1   mol ratio), compact and full-coverage perovskite film with large grain sizes (>1   µm) are obtained, and the speed of perovskite film formation is greatly accelerated. Moreover, the film prepared in a 1:1   mol ratio of the two precursors exhibits good moisture liability for several days under around 70% RH environment. As a result, the PbCl 2 : Pb(Ac) 2 ·3H 2 O (1:1) results in the highest efficiency of 14.77%. The findings in this work provide a facile way to improve the perovskite film quality and stability.