One-Step Solvent-Free Mechanochemical Incorporation of Insoluble Cesium Salt into Perovskites for Wide Band-Gap Solar Cells

The preparation of high-quality perovskite thin films with a low concentration of defects has recently been achieved through cation engineering using, for example, Cs halide salts. However, many Cs salts cannot be adopted readily due to their frequent insolubility in typical N,N-dimethylformamide (DMF) or dimethyl sulfoxide (DMSO) solvent systems. Herein, we report the application of green, rapid, and solvent-free mechanosynthetic ball-milling...