Eu2+ doped halide perovskite KCaCl3 with high-efficiency blue emission and scintillation application

Abstract

Doping engineering in lead-free all-inorganic halide perovskites plays an important role in their performance modulation for emerging photonics applications. Benefiting from the weak electron phonon coupling effect, and the distorted site occupied by Eu²⁺, chloride perovskite phosphor KCaCl₃ : Eu²⁺ is prepared and demonstrated herein, which shows high-efficiency (internal quantum efficiency, IQE = 96.1%) blue emission peaking at ∼430 nm as well as good thermal stability (74%@ 423 K of the initial integrated intensity at 298 K). This phosphor also has high radiation luminescence intensity (∼7.1 times that of commercial Lu₃Al₅O₁₂ : Ce³⁺) upon X-ray excitation and a low detection limit (483.5 nGy_air s⁻¹), exhibiting good potential in X-ray detection and imaging. This work provides new insights into the design of Eu²⁺ activated halide perovskite luminescent materials for versatile optoelectronic applications.