Phenylethylammonium-formamidinium-methylammonium quasi-2D/3D tin wide-bandgap perovskite solar cell with improved efficiency and stability

•PEA cation substitution in WBG Sn perovskite through compositional engineering.•2D/3D perovskite forms which support preferential growth with high crystallinity.•Reduced trap density with proper band-alignment led to efficient charge extraction.•Moisture penetration reduced in 2D/3D and increased ambient stability of film.•Respectable efficiency of 7.96% has been achieved for 2D/3D WBG sn-based PSC.