Indication of CsPbBr3 inclusions in zero dimensional Cs4PbBr6 perovskite single crystals by alkylammonium post‐treatment

Abstract

Abstract The zero‐dimensional Cs4PbBr6 perovskites are highly emissive materials that demonstrated an effective potential in light emitting applications. There is an on‐going debate regarding the origin of its strong and green photoluminescence, which is not in line with the expectedly wide band‐gap energy of the strongly confined material. Herein, using mortar and pestle, we react Cs4PbBr6 single crystals with methanol solutions of ammonium barrier molecules, and affect their optical and compositional properties. The ammonium barrier molecules react with the 0D Cs4PbBr6 crystals, and lead to a structural transformation of the CsPbBr3 inclusions into two‐dimensional perovskite within the 0D phase of the Cs4PbBr6. In addition, the photoluminescence quantum yield was increased as a result of the post treatment. This can explain the origin of the strong, green photoluminescence from these crystals. This novel post‐treatment affects the properties of the CsPbBr3 inclusions in Cs4PbBr6 crystals by a straightforward process, which can be utilized to another 0D perovskite.

Keywords

• Cs4PbBr6
• green emission
• grinding
• perovskite
• zero dimensional