Efficient plasmon-hot electron conversion in Ag\u2013CsPbBr3 hybrid nanocrystals

Xinyu Huang,Zhangzhang Chen,Hongbo Li,Xiaoyong Wang,Chunfeng Zhang,Lan Chen,Min Xiao,Zhenda Lu,Shijing Tan

doi:10.1038/s41467-019-09112-1

Abstract

Hybrid metal/semiconductor nano-heterostructures with strong exciton-plasmon coupling have been proposed for applications in hot carrier optoelectronic devices. However, the performance of devices based on this concept has been limited by the poor efficiency of plasmon-hot electron conversion at the metal/semiconductor interface. Here, we report that the efficiency of interfacial hot excitation transfer can be substantially improved in hybrid metal semiconductor nano-heterostructures consisting of perovskite semiconductors. In Ag–CsPbBr3 nanocrystals, both the plasmon-induced hot electron and the resonant energy transfer processes can occur on a time scale of less than 100 fs with quantum efficiencies of 50 ± 18% and 15 ± 5%, respectively. The markedly high efficiency of hot electron transfer observed here can be ascribed to the increased metal/semiconductor coupling compared with those in conventional systems. These findings suggest that hybrid architectures of metal and perovskite semiconductors may be excellent candidates to achieve highly efficient plasmon-induced hot carrier devices.

Highlights

Many factors may be involved, the markedly high quantum efficiency of hot-excitation transfer in Ag–CsPbBr3 NCs can be primarily ascribed to the strong coupling between metal and semiconductor
In previous plasmon-derived systems with metal–semiconductor or metal-molecule structures, the oscillation strength associated with local Surface plasmon resonance (SPR) is generally much higher than that of a single-electron transition in the semiconductor/ molecule part, which limits the efficiency of hot-excitation transfer
We have connected the population of electron–hole pairs (EHPs) and charge-separated state induced by plasmonic excitation to the PIRET and HET processes, respectively

Summary

Introduction

Collecting the energy of hot electrons by contacting metallic nanostructures with molecules or semiconductors can be integrated in optoelectronic devices for photovoltaic[4,5,6,7], photodetection[8,9,10,11], and photocatalytic applications[4,7,12,13,14,15,16,17,18,19,20,21] This new design paves a way to realize hot-carrier devices whose performance may potentially exceed those of conventional devices. Heterostructures consisting of metal and semiconductor nanoparticles have been widely studied for plasmon-derived hotelectron devices (i.e., the metal–semiconductor Schottky junction devices)[8,9,10,11] The performances of such devices strongly depend on the efficiencies of plasmon-hot electron conversion at the metal–semiconductor interfaces. The high efficiency of HET (~50 ± 18%) and the resultant a c

Methods

Results

Conclusion