Research on photoelectrochemical photodetectors based on bismuth 2d thin films
Kailong Han, Guoyi Huang, Yiding Jia, Qijie Niu, Zhaoqiang Zheng, Bing Wang
Abstract
In recent years, two-dimensional (2D) materials have garnered considerable attention in the field of photodetection due to their advantageous characteristics, including an adjustable bandgap, high carrier mobility, and compatibility with silicon-based technology. Popular choices for high-performance photodetectors include graphene, black phosphorus, and molybdenum disulfide among the various available 2D materials. Notably, single-element 2D materials such as graphene, tellurene, and phosphorene (collectively referred to as "Xene") show particular promise. This study focuses on the fabrication of thin films of 2D bismuth material using the pulsed laser deposition (PLD) technique, with the goal of constructing a photoelectrochemical (PEC)-type photodetector. PLD offers several advantages, such as reduced processing time, larger material coverage, and reduced contamination risks. The photodetector based on the PLD-fabricated bismuth thin films demonstrates stable photoresponse and exhibits superior characteristics compared to photodetectors prepared using liquid-phase exfoliation methods. Additionally, the PEC photodetector exhibits self-powering capabilities, eliminating the need for external voltage application. An innovative aspect of this study lies in the utilization of pulsed laser deposition for depositing 2D bismuth material films, enabling improved control over material thickness and a streamlined processing approach. The resulting PEC photodetectors outperform previously reported devices in terms of response time, responsivity, and photocurrent.