Bismuth nanoplatelets: universal synthetic strategy and emerging application for PEC-type photodetectors

Bi nanoplatelets (NPLs) with a narrow size distribution and high yield have been successfully fabricated by a novel two-step sonication-assisted solvothermal method. Applied as photo-electrochemical (PEC)-type photodetectors (PDs), it is shown that the Bi NPLs exhibit a pronounced photo-response ranging from the ultraviolet to the visible regions. The photo-response performance of Bi NPLs-based PDs was adjusted by external conditions and interpreted by density functional theory calculations in terms of the formation of the respective Bi-based compounds. The PEC results demonstrate that the optimal photocurrent density (P-ph) and photoresponsivity (R-ph) can reach 12.27 mu A/cm(2) and 3016 mu A/W in alkaline electrolytes, respectively. Besides, the Bi NPLs-based PDs exhibit superb long-term cycling stability (similar to 97.86% remained after 1000 cycles). We conclude that Bi NPLs demonstrate great promise as an emerging building block for the design of high-performance PEC-type PDs as well as other novel optoelectronic devices, holding the potential for breakthrough developments in these fields. (c) 2023 Published by Elsevier Ltd.

Automated summary

Bi nanoplatelets (NPLs) with narrow size distribution and high yield were fabricated by a novel two-step sonication-assisted solvothermal method. The Bi NPLs exhibited pronounced photo-response from ultraviolet to visible regions when used as photo-electrochemical (PEC)-type photodetectors (PDs). The photo-response performance of Bi NPLs-based PDs was adjusted by external conditions and interpreted by density functional theory calculations. The optimal photocurrent density (P-ph) and photoresponsivity (R-ph) of Bi NPLs-based PDs reached 12.27 µA/cm² and 3016 µA/W in alkaline electrolytes, respectively. Moreover, the Bi NPLs-based PDs demonstrated superb long-term cycling stability (around 97.86% remained after 1000 cycles). Bi NPLs show great promise as a building block for high-performance PEC-type PDs and other optoelectronic devices.