Efficient Blue Emission in Organic–Inorganic Metal Halide (TEA)2InCl5 Triggered by Bi3+‐Doping

Abstract Lead‐free 0D In‐based organic–inorganic metal halides (OIMHs) have attracted tremendous attention because of their nontoxicity, environmental stability, and excellent photoluminescence properties. However, it remains controversial and unclear whether the luminous division exists in ns 2 doping In‐based materials, as the majority of In‐based materials are considered non‐luminous. Herein, a series of Bi 3+ ‐doped (TEA) 2 InCl 5 (TEA = tetraethylammonium) crystals are synthesized and it is determined that the blue emission stemmed from Bi ions. Remarkably, the photoluminescence quantum yield (PLQY) of the blue emission at 469 nm reached 69.69% under 371 nm excitation, exceeding those of previously reported Bi 3+ ‐doped OIMHs. In addition, pristine and Bi 3+ ‐doped compounds exhibited excellent structure and optical stability under humid conditions. This study provides new insights into the photoluminescence properties of In‐based OIMHs, especially regarding the high‐efficiency emission of Bi 3+ ‐doped materials.