A promising alternative solvent of perovskite to induce rapid crystallization for high-efficiency photovoltaic devices

Abstract

As solar cell structures based on planar heterojunctions have already demonstrated very impressive advances in cost-effectiveness and performance, many different solvents are being developed and gradually adopted for high-performance inorganic–organic hybrid perovskite solar cells. Here, we introduce a simple planar cell configuration with layers prepared in a fully solution-based process, in which dimethylacetamide (DMAC) serves as an effective precursor solvent that is comparable with N,N-dimethylformamide (DMF). The use of DMAC leads to a smooth and dense perovskite film via one-step deposition, whose ideal morphology enables solar cells to obtain a high power-conversion efficiency of 15.12%. We also studied the effect of different solvents through a computation of the stabilization energy between PbI₂, CH₃NH₃I, and solvent molecules. These results offer insight into the promising directions for the development of solvent engineering.