Theoretical Design of Tellurium-Based Two–Dimensional Perovskite Photovoltaic Materials

In recent years, the photoelectric conversion efficiency of three–dimensional (3D) perovskites has seen significant improvements. However, the commercial application of 3D perovskites is hindered by stability issues and the toxicity of lead. Two–dimensional (2D) perovskites exhibit good stability but suffer from low efficiency. Designing efficient and stable lead–free 2D perovskite materials remains a crucial unsolved scientific challenge. This study, through structural prediction combined with first–principles calculations, successfully predicts a 2D perovskite, CsTeI₅. Theoretical calculations indicate that this compound possesses excellent stability and a theoretical efficiency of up to 29.3%, showing promise for successful application in thin–film solar cells. This research provides a new perspective for the design of efficient and stable lead-free 2D perovskites.