Superior Stability of CsPbBr₃ Films under High-Energy Proton Irradiation

Abstract

This study examines the effects of high-energy (1.4 to 15.5 MeV) proton irradiation on CsPbBr 3 thin films, focusing on the significant transformations that occur beyond a critical dose threshold of 1 × 10 15 protons cm −2 . Below this dose, the material maintains its structural and optical properties, demonstrating high irradiation stability. However, when exposed to doses exceeding this threshold, CsPbBr 3 undergoes notable changes, including the formation of CsPb 2 Br 5 , a decrease in bromine content, and significant particle growth, primarily driven by local thermal spikes and enhanced bromine mobility. The irradiation-induced particle growth improves photoluminescence characteristics and increases the quantum yield and extended emission lifetimes due to reduced nonradiative recombination. These findings highlight the dual nature of CsPbBr 3 under proton irradiation, its inherent stability below a critical proton dose and its remarkable adaptive self-healing capabilities above it, underscoring its suitability for high-radiation applications.