White Light Emission in Europium‐Doped Inorganic Perovskite Single Matrix

Abstract The realization of stable single‐component white light emission in metal halide perovskites is still challenging due to the fast halide ion migration and narrow luminescence bands. In this work, all‐inorganic single CsPbCl x Br 3−x perovskite microplates with stable red‐blue‐green triple color light emission are prepared by introducing europium ions Eu 3+ as dopants. Eu doping effectively suppresses ion migration and enables two spatially separated halide phases with stable dual‐wavelength emissions. Furthermore, the incorporation of Eu 3+ compensates for the absence of red‐light emission, thereby yielding a superior white emission with exceptional quality. The color rendering index of triple‐color‐emitting perovskites can be tuned successfully by controlling the halogen ratios, and the optimal microplate achieved a Commissions Internationale de l’Eclairage (CIE) coordinates of (0.32, 0.32). The results present a new enlightenment for the preparation of low‐cost single‐component white light materials.