Enhanced Performance of Si MIS Photocathodes Containing Oxide-Coated Nanoparticle Electrocatalysts.

Electrodepositing low loadings of metallic nanoparticle catalysts onto the surface of semiconducting photoelectrodes is a highly attractive approach for decreasing catalyst costs and minimizing optical losses. However, securely anchoring nanoparticles to the photoelectrode surface can be challenging-especially if the surface is covered by a thin insulating overlayer. Herein, we report on Si-based photocathodes for the hydrogen evolution reaction that overcome this problem through the use of a 2-10 nm thick layer of silicon oxide (SiO) that is deposited on top of Pt nanoparticle catalysts that were first electrodeposited on a 1.