Electrocatalysis of Furfural Oxidation Coupled with H2 Evolution via Nickel-Based Electrocatalysts in Water

Electrocatalytic water splitting has been widely considered as a promising approach to produce clean H-2. The anodic half reaction of water splitting, the O-2 evolution reaction (OER), is the kinetic bottleneck of the overall process and its product O-2 is not of high value. Herein, we report a novel strategy to replace OER with a thermodynamically more favorable anodic reaction, furfural oxidation to 2-furoic acid. Furfural is one of the dehydration products of biomass and its oxidation product 2-furoic acid has many industrial applications. A bifunctional electrocatalyst of Ni2P-derived arrays on nickel foam (Ni2P/Ni/NF) was developed for the integrated electrocatalysis of both furfural oxidation and H-2 production. When Ni2P/Ni/NF acts as the electrocatalyst for both anode and cathode, nearly 100% Faradaic efficiencies for H-2 evolution and furfural oxidation were obtained. Such an integrated electrolysis catalyzed by Ni2P/Ni/NF required an applied voltage approximate to 110mV smaller than that of pure water splitting to achieve the current density of 10mAcm(-2), together with robust stability. Overall, our novel electrolyzer produced valuable products at both electrodes (H-2 at cathode and 2-furoic acid at anode) and may extend to the coupling of H-2 evolution with many other valuable organic oxidation reactions.