Retardation of Perovskite Crystal Growth by Lead Thiocyanate Addition and Its Effect on Perovskite Solar Cell Performance

The control of crystallization process of perovskite plays an important role in the performance improvement of PSCs (perovskite solar cells). In this work, we prepared perovskite by the addition of lead thiocyanate (Pb(SCN)2) to a perovskite precursor solution and investigated its effect on the performance of PSCs consist of FTO/TiO2/ZrO2/carbon structure. It was found that the crystallization process of perovskite by Pb(SCN)2 addition was very slow, which was confirmed by XRD analysis that it took at least 24 h to complete the conversion to perovskite. The maximum efficiency of PSCs with carbon electrode manufactured using Pb(SCN)2 additive was 15.6%. The analysis showed that Pb(SCN)2 addition contributes to the performance improvement of devices by delaying the crystallization rate of perovskite, increasing the crystal size and suppressing the non-radiative recombination.