Investigation of Hydrogen Gas Sensing Properties of WSe₂, Ag₂Se, WSe₂/Ag₂Se Nanostructured Electrodes Synthesized by Electrochemical Methods

In this study, WSe₂, Ag₂Se, and WSe₂/Ag₂Se nanostructured electrodes were synthesized via an electrochemical deposition method, and their hydrogen gas sensing performances were systematically investigated. The synergistic interaction between WSe₂ nanosheets and Ag₂Se nanoparticles significantly enhanced charge transport and catalytic activity in the hybrid electrode. Compared to the pristine WSe₂ and Ag₂Se electrodes, the hybrid electrode exhibited a remarkably higher current response of 7.89 mA cm^-2 at 5000 ppm of H₂ and demonstrated stable and reversible sensing behavior over a wide range of hydrogen concentrations (1000-5000 ppm). Analyses of SEM, Raman, and UV-Vis data revealed an increased surface area and improved electronic coupling within the hybrid structure. Furthermore, EIS and OCP measurements confirmed accelerated interfacial charge transfer and superior electrochemical stability. Overall, this study introduces a novel electrochemically synthesized WSe₂/Ag₂Se hybrid nanostructure exhibiting excellent sensing performance at low temperatures (25-150 °C) and provides a promising strategy for the development of low-power, highly stable hydrogen gas sensors.