Photothermal RuNiFeOx/FeNi3 heterostructured arrays with Janus wettability for highly enhanced oxygen evolution reaction

Renewable electricity driven water splitting is a promising way for clean hydrogen production, but the practical application of this technology is greatly impeded by the sluggish kinetics of the anodic oxygen evolution reaction (OER). Considering a typical endothermic nature of water splitting that is highly sensitive to temperature, herein, we introduce a simple,   convenient   and non-contact in situ self-heating mode to combine with OER-active electrocatalysts, enabling the reduced reaction energy barrier and the enhanced electrocatalytic performances. The RuNiFeO x /FeNi 3 heterostructures are designed and grown on iron foam (IF) substrate using a facile redox corrosion strategy followed by the controllable heat treatment. The RuNiFeO x /FeNi 3 heterostructures with the narrow bandgap characteristic can generate a distinctive photothermal effect. The local temperature of electrode surface can immediately increase under NIR light irradiation, offering an impressive self-heating platform to promote OER catalysis. The RuNiFeO x /FeNi 3 /IF significantly reduces the OER overpotential by the combination with photothermal effect. Meanwhile, the RuNiFeO x /FeNi 3 /IF demonstrates the stable and reproducible photothermal-electrocatalytic behaviors. This research offers a new vision for the rational design of advanced electrocatalytic systems coupled with photothermal effect to lower activation energy barriers and promote electrocatalysis of water splitting.