Two‐Dimensional Perovskites with Tunable Room‐Temperature Phosphorescence

Abstract Functional materials with room‐temperature phosphorescence (RTP) are highly desired for optoelectronic and bio‐imaging applications. Currently, most inorganic RTP materials require exceedingly expensive rare metals. Although organic materials have the advantages of low cost and facile fabrication, their quantum yields are quite poor due to low efficiency in the intersystem crossing process. 2D hybrid organic‐inorganic perovskites (2D HOIPs), however, entail the virtue of both inorganic and organic RTP materials, thereby capable of strong and persistent phosphorescence for making future‐generation RTP materials. Herein, an effective screening approach is presented to search for 2D HOIPs as efficient RTP materials. The guidelines for this high‐throughput screening include the Dexter‐type energy transfer mechanism, the computed excited‐state properties, and the molecular morphing operators. Moreover, the structural stability of the 2D HOIPs is assessed by using a newly proposed tolerance factor. Overall, 539 candidates are identified as promising 2D HOIP materials for RTP. In particular, four 2D HOIPs, namely, (thNfuEA)₂PbBr₄, (selBthEA)₂PbBr₄, (selBfuEA)₂PbBr₄, and (BselBthEA)₂PbBr₄, are predicted to possess robust room‐temperature stability, suitable energy level and proper frontier‐orbital alignment, thus hold high potential for functional optoelectronic applications.