Room Temperature Synthesis of All Inorganic Lead-Free Zero-Dimensional Cs4SnBr6 and Cs3KSnBr6 Perovskites

Abstract

Lead halide perovskites are excellent candidates for photoelectronic and photovoltaic applications, but the toxicity from lead is extremely concerning. Recently, Sn-based zero-dimensional lead-free perovskites synthesized using solid-state reaction techniques have become a new focus in the field. Here, we report a simple room temperature antisolvent method for the synthesis of all inorganic lead-free green emissive Cs<inf>4</inf>SnBr<inf>6</inf> (emission at 524 nm) and cyan emissive Cs<inf>3</inf>KSnBr<inf>6</inf> (emission at 500 nm) zero-dimensional perovskites. Their photoluminescence quantum yields reach 20% and 35%, respectively. In addition, they maintain their emission for 46 and 55 h in the air, respectively, compared to only 5 min of CsSnBr<inf>3</inf>. This method provides a convenient way to do the research and apply these highly emissive perovskites.