摘要
In this study, we renovated the sequential deposition route to fabricate a high-quality methylammonium lead iodide (MAPbI 3 ) capping layer in scaffold-type PSCs from a low-toxicity aqueous lead nitrate precursor system. Through interpretation of the slow and stepwise conversion mechanism from lead nitrate to MAPbI 3 in a methylammonium iodide bath, two key innovations, namely chloride inclusion in the methylammonium iodide bath and multiple-cycle immersion, were applied to remedy the flaws in the original MAPbI 3 film. The PSC fabricated from the aqueous lead nitrate precursor through this renovated process showed remarkable stability over 55 days in an ambient dark chamber. Our work clearly indicates that using water as a processing solvent is irrelevant to the conversion efficiency or stability of a PSC and demonstrates no difference in the quality of PSC made by PbI 2 /DMF protocol. This water-processed, environmentally friendly precursor system lights a direction of clean production of PSC using a minimal quantity of harmful organic solvents.