This work contributes to further understand the complex multistep HER from light absorption to charge transfer to protons, helping to develop cost-effective and efficient photocathodes.

The physically stable adhesion of catalysts was also achieved despite the в€ј40 nm thick catalysts owing to the interfacial Ag nanostructure. Ag modulated the surface electronic property of MoSx to improve the reaction kinetics as well as helped a charge transport at the Ag|p-Si(100) junction. The nanostructured porous Ag layer was introduced by a simple chemical process, followed by photoelectrochemical deposition of MoSx to form MoSx/Ag nanostructures in cross-shaped catalyst pattern arrays. We demonstrate Ag as a 3D interfacial nanostructure of patterned MoSx catalysts for photoelectrochemical HER. The interfacial layer efficiently extracts the electrons from the semiconductor and conveys those to the catalytically active surface. One of the methods to simultaneously satisfy these conditions is to adopt an interfacial layer between the semiconductor and active materials in HER. Moreover, catalysts, especially non-noble materials that demand a large amount of loading, should be adequately dispersed on the semiconductor surface to allow sufficient light absorption to generate excitons. Additionally, their thermodynamic property and physical adhesion should be compatible with the underlying semiconductor for favorable band alignment and stability during vigorous H2 bubble formation. In catalytic materials, an intrinsic activity with fast charge-transfer kinetics is important.

The design of a catalyst/semiconductor junction for the hydrogen evolution reaction (HER) requires various factors for high performance. Photoelectrochemical cells represent one of the promising ways to renewably produce hydrogen (H2) as a future chemical fuel.

Band In A Box 6.0. 4 J