Organic Thermoluminescence Driven by Electron Back Transfer: Microsecond Explosive Emission to Persistent Multi‐Hour Afterglow

Abstract Precise control over the release of light energy, distinct from conventional thermal energy management, poses significant challenges in luminescent technologies. This study pioneers organic above‐room‐temperature thermoluminescent materials using radical pairs as energy storage centers (ESCs), enabling controlled light energy release from multi‐hour afterglows to microsecond‐scale explosive bursts, accelerating the energy release rate by up to 1.8 × 10 8 times. Notably, the unique transannular interactions between sulfur and oxygen in thianthrene oxides facilitate a thermally driven back electron transfer (BET) process based on radical pairs, central to the energy storage and release mechanism. Due to this BET process, these materials precisely modulate luminescence and exhibit robust stability, maintaining luminescence for 4 h in boiling water and storing energy in air for over six months. These findings advance organic thermoluminescence, highlight the significance of BET processes in various domains, and set new performance benchmarks for luminescent materials under extreme conditions.