Growth of AgI semiconductors on tailored 3D porous Ti3C2 MXene/graphene oxide aerogel to develop sensitive and selective signal-on photoelectrochemical sensor for H2S determination

Long term exposure to hydrogen sulfide (H2S) even in low concentration poses a serious threat to human health and the ecosystem, pointing to the significance for its effective supervision. In this study, we report a sensitive and selective signal-on photoelectrochemical (PEC) sensor for the determination of toxic H2S in aqueous solution by in situ growth of AgI semiconductors on tailored three-dimensional (3D) porous Ti3C2 MXene/graphene oxide aerogel (MGA). Our research demonstrated that the resultant MGA with the starting feeding mass ratio of MXene and graphene oxide (GO) of 1:8 (MGA1:8) possessed the most excellent PEC performance after the growth of AgI semiconductors than their monomers (Ti3C2 MXene and GO) and the MGAs with other starting feeding mass ratio. Such designed PEC sensor based on MGA1:8/AgI heterojunction showed dramatically strengthened PEC responses with increasing concentrations of S2-. Correspondingly, a wide linear range of 5 nM-200 mu M, a low limit of detection of 1.54 nM (S/N = 3), and exclusively unique selectivity have been achieved. Our research illustrates that the PEC sensor designed with tailored MGA constitutes is an effective pathway to enhance the overall sensing performance, which will envision to boost more efforts for advanced 3D porous aerogel using in PEC sensors.

Automated summary

Long term exposure to low concentration of hydrogen sulfide (H2S) poses serious health risks and the need for effective supervision. This study presents a sensitive and selective photoelectrochemical (PEC) sensor for detecting toxic H2S in water using AgI semiconductors grown on tailored three-dimensional (3D) porous Ti3C2 MXene/graphene oxide aerogel (MGA). The designed PEC sensor, based on MGA1:8/AgI heterojunction, demonstrated enhanced PEC responses with increasing concentrations of S2-, achieving a wide linear range, a low detection limit, and unique selectivity. This research highlights the effectiveness of tailored MGA in enhancing the overall sensing performance, promoting further advancements in 3D porous aerogels for PEC sensors.