Semiconducting Nanoparticles: Single Entity Electrochemistry and Photoelectrochemistry.

S Mathuri,Xiuting Li,Mudaliar Mahesh Margoni,Yuanhang Zhu

doi:10.3389/fchem.2021.688320

Abstract

Semiconducting nanoparticles (SC NPs) play vital roles in several emerging technological applications including optoelectronic devices, sensors and catalysts. Recent research focusing on the single entity electrochemistry and photoelectrochemistry of SC NPs is a fascinating field which has attained an increasing interest in recent years. The nano-impact method provides a new avenue of studying electron transfer processes at single particle level and enables the discoveries of intrinsic (photo) electrochemical activities of the SC NPs. Herein, we review the recent research work on the electrochemistry and photoelectrochemistry of single SC NPs via the nano-impact technique. The redox reactions and electrocatalysis of single metal oxide semiconductor (MOS) NPs and chalcogenide quantum dots (QDs) are first discussed. The photoelectrochemistry of single SC NPs such as TiO2 and ZnO NPs is then summarized. The key findings and challenges under each topic are highlighted and our perspectives on future research directions are provided.

Highlights

Semiconductor nanomaterials have attracted increasing interest due to their excellent physical and chemical properties comparing with their bulk counterparts, such as continuous absorption bands, narrow and intensive emission spectra, high chemical and photo-bleaching stability, processability and surface functionality, which make them suitable candidates in single electron devices, sensors, imaging devices, solar cells, nano-electronics, optoelectronic devices and memory devices (Itoh et al, 1988; Wang and Herron, 1991; Bhargava et al, 1994; John and Singh, 1996; Singh and John, 1997)
A greater mechanistic understanding of the electrochemical and photo-electrochemical reactivity of nanomaterials requires the development of method for probing electron transfer events on single redox nanomaterials and individual catalytic entities
To understand the environmental fate of CuO nanoparticles and further correctly assess their toxicity, Zampardi et al employed the nano-impact method to investigate the electrochemical behavior of single copper oxide nanoparticles in the presence of anionic species (Cl− and NO3−) commonly found in real water media

Summary

Introduction

Semiconductor nanomaterials have attracted increasing interest due to their excellent physical and chemical properties comparing with their bulk counterparts, such as continuous absorption bands, narrow and intensive emission spectra, high chemical and photo-bleaching stability, processability and surface functionality, which make them suitable candidates in single electron devices, sensors, imaging devices, solar cells, nano-electronics, optoelectronic devices and memory devices (Itoh et al, 1988; Wang and Herron, 1991; Bhargava et al, 1994; John and Singh, 1996; Singh and John, 1997). Has been investigated via nano-impact method (Sardesai et al, 2013; Tschulik and Compton, 2014; Shimizu et al, 2016a; Shimizu et al, 2016b; Zhou et al, 2017; Zampardi, et al, 2018; Peng et al, 2018; Xie et al, 2020; Karunathilake et al, 2020) The specific research topics mainly involve two aspects: the electrochemical redox behavior and electrocatalysis of single MOS, which is summarized and discussed in the following paragraphs respectively.

Results

Conclusion