Engineering a Cu2O/NiO/Cu2MoS4 hybrid photocathode for H2 generation in water

Abstract

We report a scalable process for fabricating a multiple-layer hybrid photocathode, namely Cu₂O/NiO/Cu₂MoS₄, for H₂ generation in water. In pH 5 solution and under 1 sun illumination, the photocathode showed interesting photocatalytic properties. The onset photocurrent was recorded at +0.45 V vs. RHE, while at 0 V vs. RHE, a photocurrent density of 1.25 mA cm⁻² was obtained. It was found that the NiO interlayer enhances charge transfer from the Cu₂O light harvester to the Cu₂MoS₄ hydrogen evolution reaction electrocatalyst which in turn accelerates charge transfer at the electrode/electrolyte interface, and therefore improves the photocatalytic properties of the Cu₂O photocathode.