Trap‐Assisted Mechanoluminescence in Mn ²⁺ ‐Doped Transparent Amorphous Glass for Potential Stress Sensing

Abstract Mechanoluminescence (ML) materials have shown great promise in stress sensing, structural monitoring, information encryption etc., but are primarily based on crystalline material with limited processability, environmental stability, and optical transparency, which seriously hinder their applications. Here, a highly transparent Mn ²⁺ ‐doped amorphous glass system with significant ML properties is designed. A composition modulation strategy is proposed to engineer structural defects within the glass network structure, which ensures more numerous defects to activate the ML of Mn ²⁺ . Under repeated charging–discharging cycles, the samples present remarkable ML repeatability and recovery performance, and the ML intensity demonstrates a zero‐quenching performance after being placed in various solutions for 14 days. Combined with the Raman, EPR spectra, and TL experiments, the inherent relationship between ML performance and the traps is clarified, where the oxygen vacancies are responsible for the generation of ML. Based on the ideal ML performance and high transparency of the designed amorphous glass, the application prospects in stress identification and detection are evaluated. This work provides a design principle to accelerate the development of transparent ML glass materials toward versatile photonic applications.