This study focuses on tin (Sn)‐based halide perovskite CsSnI 3 , aiming to mitigate the environmental toxicity associated with lead‐containing perovskites and to explore potential applications in optoelectronic devices. Considering the challenges of easy oxidation and poor thermodynamic stability in pristine Sn‐based perovskites, rare‐earth elements doping is proposed to regulate the structure and properties of CsSnI 3 . The unique electronic orbital characteristics of rare‐earth elements dopants can effectively influence atomic bonding, thereby significantly tuning the thermodynamic stability. Meanwhile, the local lattice distortion induced by rare‐earth elements incorporation further redistributes the charge density around the dopant site, thereby suppressing oxidation and enhancing chemical stability. The theoretical calculations reveal that rare‐earth elements doping can also significantly change the electronic properties through the involvement of d ‐orbital electrons. Moreover, optical analysis indicates that rare‐earth elements doping mainly induces noticeable modulation of the dielectric function and enhances the optical response in the relatively low‐energy region. This work provides a theoretical foundation and computational guidance for enhancing the stability and optoelectronic performance of Sn‐based perovskites through precise doping strategies, offering new insights into the development of high‐performance, lead‐free, and environmentally friendly optoelectronic devices.
Wang et al. (Mon,) studied this question.