Interfacial Engineering of Ni/Ni0.2Mo0.8N Heterostructured Nanorods Realizes Efficient 5-Hydroxymethylfurfural Electrooxidation and Hydrogen Evolution

Simultaneously achieving electrochemical conversion of biomass -derived molecules into value-added products and energy-efficient hydrogen production is a highly attractive strategy but challenging. Herein, we reported a heterostructured Ni/Ni0.2Mo0.8N nanorod array electrocatalyst deposited on nickel foam (Ni/Ni0.2Mo0.8N/NF), which exhibited excellent electrocatalytic activity toward 5-hydroxymethylfurfural (HMF) oxidation, and nearly 100% conversion of HMF and 98.5% yield of 2,5-furandicarboxylic acid (FDCA) products can be achieved. The post-reaction characterizations unveil that Ni species in Ni/ Ni0.2Mo0.8N/NF would be readily converted to NiOOH as the real active sites. Furthermore, a two-electrode electrolyzer was assembled with Ni/Ni0.2Mo0.8N/NF utilized as a bifunctional electrocatalyst for both the cathode and anode, giving rise to a low voltage of 1.51 V to concurrently produce FDCA and H2 at 50 mA cm-2. This work enlightens the significance of regulating redox activities of transition metals via interfacial engineering and constructing heterostructured electrocatalysts toward more efficient energy utilization.

Automated summary

This study reported a heterostructured Ni/Ni0.2Mo0.8N nanorod array electrocatalyst, which exhibited excellent electrocatalytic activity for the oxidation of 5-hydroxymethylfurfural (HMF) and achieved nearly 100% conversion of HMF and 98.5% yield of 2,5-furandicarboxylic acid (FDCA) products. Further experiments revealed that Ni species in the catalyst can be readily converted to NiOOH as the real active sites. In addition, a two-electrode electrolyzer assembled with this catalyst achieved simultaneous production of FDCA and H2 at a low voltage. This work highlights the significance of regulating redox activities of transition metals and constructing heterostructured electrocatalysts for more efficient energy utilization.