Photoemission of the Upconverted Hot Electrons in Mn-Doped CsPbBr 3 Nanocrystals

作者：Chih‐Wei Wang, Xiaohan Liu, Tian Qiao, Mohit Khurana, А. В. Акимов, Dong Hee Son · 发表于：Nano Letters · 年份：2022 · DOI：10.1021/acs.nanolett.2c02342 · 被引用次数：23 · 研究领域：Perovskite Materials and Applications、Quantum Dots Synthesis And Properties、Luminescence Properties of Advanced Materials

Hot electrons play a crucial role in enhancing the efficiency of photon-to-current conversion or photocatalytic reactions. In semiconductor nanocrystals, energetic hot electrons capable of photoemission can be generated via the upconversion process involving the dopant-originated intermediate state, currently known only in Mn-doped cadmium chalcogenide quantum dots. Here, we report that Mn-doped CsPbBr 3 nanocrystals are an excellent platform for generating hot electrons via upconversion that can benefit from various desirable exciton properties and the structural diversity of metal halide perovskites (MHPs). Two-dimensional Mn-doped CsPbBr 3 nanoplatelets are particularly advantageous for hot electron upconversion due to the strong exciton–dopant interaction mediating the upconversion process. Furthermore, nanoplatelets reveal evidence for the hot electron upconversion via long-lived dark excitons in addition to bright excitons that may enhance the upconversion efficiency. This study establishes the feasibility of hot electron upconversion in MHP hosts and demonstrates the potential merits of two-dimensional MHP nanocrystals in the upconversion process.