Promoting the charge separation and photoelectrocatalytic water reduction kinetics of Cu2O nanowires via decorating dual-cocatalysts

Developing high activity and low-cost materials to produce hydrogen by the sustainable way of photoelectrochemical is key to social development. The abundance and inexpensive Cu2O has been received increasing research as its suitable energy level for photocatalytic water reduction. However, the fast charge recombination rate and the sluggish catalytic kinetics are the huge challenges facing the Cu2O photoreduction. Here, the highly reactive Cu2[email protected]2 photocathode is constructed by depositing dual-cocatalysts of the carbon layer and MoS2 nanosheets on Cu2O nanowires to realize efficient water reduction. An impressive carrier concentration of 6.59 × 1023 cm−3 is received, which is 2.78 times of the bare Cu2O, resulting in remarkable enhancement in photocurrent density of 3.34 times for the Cu2[email protected]2 photocathode. Moreover, the applied bias photon-to-current conversion efficiency of the bare Cu2O enhanced 4.5 times from 0.16 % to 0.72 % in the Cu2[email protected]2 photocathode. The analysis shows that the Cu2O as light absorber, the carbon layer as electron transfer promoter, and MoS2 nanosheets as catalytic sites, thus facilitating chrage separation and enhancing catalytic kinetics. This system paves a feasible strategy for designing other photoelectrodes to realize efficient charge separation and high catalytic activity.