Turning on the Photoelectrochemical Responses of Cd Probe-Deposited g-C3N4 Nanosheets by Nitrogen Plasma Treatment toward a Selective Sensor for H2S

A selective photoelectrochemical (PEC) sensor has been designed for the signal-on detection of H2S using g-C3N4 nanosheets that were treated with N-2 plasma for depositing Cd probes. It was discovered that the yielded Cd/N@g-C3N4 nanocomposites could present enhanced photocurrents of specific responses to H2S under visible light irradiation, in contrast to the ones without the pretreatment of N-2 plasma showing no H2S response. Herein, the Cd probes deposited on g-C3N4 nanosheets might react with H2S to generate CdS on Cd/N@g-C3N4, forming the efficient heterojunctions. Especially, the plasma-derived N contents might act as the bridge to promote charge transfer between the generated CdS and g-C(3)N(4 )resulting in the signal-on PEC responses to H2S. A selective PEC sensor was thereby developed for sensing H2S of concentrations linearly ranging from 40.0 to 10,000 pM, with a detection limit of about 21 pM. Also, the feasibility of sensing H2S in industrial waste gas was demonstrated by recovery tests. More importantly, this N-2 plasma treatment route for g-C(3)N(4 )nanosheets may open a new door toward the construction of a Cd probe-based heterojunction for the signal-on PEC sensing platform, which is promising for the wide application in the fields of environmental monitoring, food safety, and biomedical analysis.

Automated summary

A selective photoelectrochemical sensor has been developed using g-C3N4 nanosheets treated with N-2 plasma to deposit Cd probes for signal-on detection of H2S. The Cd/N@g-C3N4 nanocomposites exhibit enhanced photocurrent responses to H2S under visible light irradiation due to the formation of efficient CdS heterojunctions. This novel sensing platform shows promise for applications in environmental monitoring, food safety, and biomedical analysis.