Effect of the halogen substitution on the interfacial properties of MAPbI3 (110)/Ti3C2T2 (001): First-principles calculations

Abstract

To improve the optoelectronic properties and charge extraction efficiency of perovskite devices, precise device design and expert interface engineering are essential. In this study, we utilized first-principles simulations to investigate the structural, electrical, and optical characteristics of the interfaces between MAPbI3 and Ti3C2T2 (T = Cl, Br, I). Our computed charge density differences indicate that the internal electric field of MAPbI3/Ti3C2T2 promotes the transfer and separation of photoinduced electrons and holes. Furthermore, the heterostructures exhibit enhanced optical absorption, with higher absorption intensity observed in the visible band. Notably, the PbI2/Ti3C2Br2 interface shows the strongest cohesive energy, charge transfer, and optical absorption among the interfaces investigated. These findings provide detailed insights into the atomic-level interfacial properties of MAPbI3/Ti3C2T2 and offer valuable theoretical recommendations for the development of novel perovskite devices.