Electrochemical-photoelectrochemical dual-mode sensing platform based on advanced Cu9S8/polypyrrole/ZIF-67 heterojunction nanohybrid for the robust and selective detection of hydrogen sulfide

Abstract

The detection of hydrogen sulfide by sensing platform is desirable but highly challenged in a single-response mode due to the obstacle of low precision. In this work, a novel dual-mode electrochemical - photoelectrochemical (PEC) sensor based on Cu9S8/polypyrrole/ZIF-67 (Cu9S8/PPy/ZIF-67) nanohybrid as a double signal probe was designed for highly selective detection of hydrogen sulfide. Interestingly, the as-prepared nanohybrid with excellent peroxidase - mimicking activities show remarkable electrocatalytical activity for hydrogen sulfide oxidation by using amperometric i-t. Importantly, another mode of PEC sensing platform was also constructed based on the increase of photocurrent of the modified photoactive electrodes in response to the in-situ generation of cobalt sulfide and oxidation of hydrogen sulfide. This nanohybrid-based dual-signal transduction mode hydrogen sulfide sensor provides a highly selective and relatively wide linear range for real-time tracking hydrogen sulfide levels, which will open a new pathway in bio-sensing system, clinical disease prevention and diagnosis.