Heterostructure of Si and CoSe2: A Promising Photocathode Based on a Non-noble Metal Catalyst for Photoelectrochemical Hydrogen Evolution

Abstract

Heterostructures of semi-metallic CoSe2 nanorods and p-Si microwires behave as an efficient photocathode for the solar-driven hydrogen evolution reaction. Photocurrents as high as 9 mA cm−2 have been achieved at 0 V vs. reversible hydrogen electrode. The high photocurrents can be attributed to low charge transfer resistance between the Si and CoSe2 interfaces and between the CoSe2 and electrolyte interfaces.