Photo-assisted electrodeposition of MoSx from ionic liquids on organic-functionalized silicon photoelectrodes for H2 generation

Abstract

This work reports on the synergistic utility of ionic liquid-based, photo-assisted electrodeposition of MoS_x onto organic-functionalized silicon photolelectrodes for dihydrogen (H₂) evolution under 1-sun illumination. The surface linker 3,5-dimethoxyphenyl covalently attached to Si(111) enhances conductivity at the substrate|electrolyte interface (impedance spectroscopy) and provides improved physico-chemical support for MoS_x deposition (SEM, Raman, PEC-deposition, XPS), to generate a functional composite device that results in 0.33% efficiency for solar → H₂ conversion. We report a new method of ionic liquid-based MoS_x deposition that avoids complications in analogous aqueous procedures and facilitates the deposition of a uniform catalytic film. This work provides a generalized framework for the optimization of non-platinum catalysts for solar → H₂ conversion.