Rationalizing the control of interfacial charge transfer directions in halide perovskite materials via additives: A first principles investigation

In this manuscript, we computationally investigate the control of the interfacial electron transfer directions in the halide perovskite materials based on CsPbBr₃. The first principles calculations suggest that by employing selected small organic molecules, the directions of the interfacial electron transfer could be successfully controlled: either from the halide perovskite substrate to the adsorbate, or from the adsorbate to the halide perovskite substrate. Such controlling of the interfacial charge transfer directions is interesting and is justified by the occupied/empty states that are introduced by the molecular additives. Further large scale theoretical work of the additive design to control of the interfacial charge transfer directions in the halide perovskite materials is called for. This theoretical study facilitates the understanding of the interfacial electron transfer directions of halide perovskite materials, which could be critical in the design of the perovskite-based optoelectronic device interfacial electron transfer directions where the control of the interfacial electron transfer directions is desired.