Robust Tin-Based Perovskite Solar Cells with Hybrid Organic Cations to Attain Efficiency Approaching 10%

The stability of a tin‐based perovskite solar cell is a major challenge. Here, hybrid tin‐based perovskite solar cells in a new series that incorporate a nonpolar organic cation, guanidinium (GA + ), in varied proportions into the formamidinium (FA + ) tin triiodide perovskite (FASnI 3 ) crystal structure in the presence of 1% ethylenediammonium diiodide (EDAI 2 ) as an additive, are reported. The device performance is optimized at a precursor...