The Dion-Jacobson perovskite CsSbCl4: a promising Pb-free solar-cell absorber with optimal bandgap similar to 1.4 eV, strong optical absorption similar to 10(5) cm(-1), and large power-conversion efficiency above 20%

摘要

Organic-inorganic hybrid Pb-based halide perovskites, especially the well-known MAPbI(3), have shown great promise for photovoltaic applications due to their fast-growing power-conversion efficiency (PCE) and low manufacturing cost. However, their poor ambient stability and Pb-toxicity are still challenging issues for future commercialization. Here, by combining first-principles calculations with large-scale screening, we propose a Pb-free all-inorganic Dion-Jacobson perovskite CsSbCl4, which has an optimal bandgap (similar to 1.4 eV) in the first place. Our calculations also show that CsSbCl4 possesses high carrier mobility (similar to 10(2)-10(4) cm(2) V-1 s(-1)) and strong interband optical absorption (similar to 10(5) cm(-1)). Consequently, its spectroscopic limited maximum efficiency can reach up to similar to 27%, similar to MAPbI(3). Moreover, the TiO2/CsSbCl4/spiro-OMeTAD junction has a PCE of 20.07%, which can be further enhanced by optimizing parameters, such as absorber defect density. These favourable characteristics of CsSbCl4 make it a potential alternative to Pb-based halide perovskites in photovoltaic devices.