Adhesion, stability, structural and electronic properties of perovskite/BaWO4 heterostructures: first-principles and experimental characterizations

Abstract

The poor stability of lead halide perovskites poses a critical challenge for realizing potential applications. Constructing latticed-matched perovskite/BaWO₄ heterostructures is highly advantageous for achieving enhanced stability. However, there is limited knowledge about the interfacial properties. Herein, we conducted combined first-principles and experimental investigations of the perovskite/BaWO₄ heterostructures in this work. First, eight different interfacial configurations were constructed and investigated systematically. The influence of surface terminations on interfacial properties was examined through the adhesive strength and electronic structures. The results of adhesion work suggest that the MAPbBr₃/BaWO₄ configurations possess stronger interfacial interaction than the CsPbBr₃/BaWO₄ configurations. The formation of BaW/PbBr and BaW/MAPb configurations was more facile compared to their counterparts. The interfacial charge transfer direction, potential difference, and valence band edges of the perovskite/BaWO₄ heterostructures were found to be significantly influenced by the surface termination of BaWO₄. The absorption intensity of the perovskite/BaWO₄ heterostructures is significantly affected by the surface termination of the perovskite. Finally, the CsPbBr₃/BaWO₄ heterostructure was fabricated and characterized, thereby validating the first-principles predictions. This study provides a fundamental contribution to establishing perovskite/BaWO₄ heterostructures for the advancement of perovskite-based optoelectronic devices.