From Pure to Sn‐Doped CsPbBr 3 : Analyzing the Evolution of Optoelectronic Properties for Improved Semiconductor Detector

ABSTRACT This study explores Sn‐doped CsPbBr 3 perovskites as advanced semiconductor materials for radiation detectors. Using density functional theory, we reveal tunable band gaps from 2.803 eV (undoped) to 1.139 eV ( Sn), enabling broad‐spectrum detection from visible light to gamma rays. Optical analysis highlights high absorption coefficients in the 4‐ to 6‐eV range and enhanced visible‐light absorption, ensuring efficient photon‐to‐electron conversion. Anisotropic dielectric properties, with increasing refractive indices and dielectric constants, improve directional sensitivity and photon capture. Phonon analysis confirms dynamic stability, ensuring robustness under operational stresses and high radiation flux. The substitution of Sn for Pb reduces toxicity, offering an eco‐friendly alternative for sustainable detector technologies. These findings establish Sn‐doped CsPbBr 3 as a versatile material for ‐ray spectroscopy, X‐ray imaging, and directional photodetectors, combining tunable optoelectronic properties, structural stability, and environmental sustainability to advance next‐generation radiation detection applications.