Thermally Stable Self‐Trapped Assisted Single‐Component White Light from Lead‐Free Zero‐Dimensional Metal Halide Nanocrystals

Abstract White‐light‐emitting single‐component materials are in high demand for lighting applications. However, achieving white light in single‐doped metal halide materials remains a challenge. Herein, for the first time, zero‐dimensional Cs₃ScCl₆:Sb³⁺(CSC:Sb³⁺) nanocrystals (NCs) are reported that exhibit bright white‐light emission, which is a result of combination of the excessive blue and yellow emissions of carbon dots and spin‐forbidden electronic transitions of Sb³⁺ ions. CSC:Sb³⁺ NCs exhibit a high photoluminescence quantum yield of 48%. Furthermore, they retain 75% of their original photoluminescence efficiency at 100 °C. This high thermal stability is mainly attributed to its lower dimensionality and high exciton binding energy as they facilitate the creation of stable white light at elevated temperatures. A single‐component white‐light‐emitting diode fabricated using CSC:Sb³⁺ NCs exhibits a high‐color rendering index and luminous efficacy values of 90 and 23 lm W⁻¹ at a high flux current of 200 mA. Therefore, the findings may pave the way for developing the next generation of white‐light‐emitting devices using a single component of white‐light‐emitting material.