Antimony -doped indium-based halide single crystals enabling white-light emission

Abstract

A metal ion doping strategy has been employed to achieve white light emission in metal halide materials; however, it is still challenging to explore lead-free metal halides. Herein, we report a series of organic–inorganic metal halide hybrids (OIMHHs) (TMPL)₃InCl₆·EtOH:xSb³⁺ (TMPL = protonated thiomorpholine, C₄H₁₀SN, x = 0–15%) exhibiting tunable emission covering the cyan to orange region along with a photoluminescence quantum yield (PLQY) increase from 1.73% to 85.35% via Sb³⁺ ion doping. Surprisingly, white light emission was successfully obtained when the Sb³⁺ concentration chosen was 0.1%. Spectroscopic analysis unveiled that the white light emission originates from a combination of organic [C₄H₁₀SN]⁺ and self-trapped exciton (STE) emission of [In(Sb)Cl₆]³⁻. Additionally, a down-convention white LED was obtained based on hybrid (TMPL)₃InCl₆·EtOH:15%Sb³⁺ due to their superior photophysical properties. Metal ion doping studied herein provides a significant design strategy for achieving single-component white light by the combination of fluorescence from the organic part and phosphorescence from the inorganic part of 0D lead-free metal hybrid halides.