Glucose electrooxidation with simultaneous H2 production on nickel-zinc electrocatalysts derived from an ethylenediamine-functionalized zeolitic imidazole framework

The oxidation of biomass-derived compounds such as glucose within electrochemical cells enables both the energy-efficient production of hydrogen and the generation of additional added-value chemicals from biomass. However, for this biomass valorization approach to become commercially viable, selective, cost-effective, and highly active electrooxidation catalysts need to be developed. In this work, we detail the synthesis of a nickel (Ni) and zinc (Zn)-based electrocatalyst for the glucose oxidation reaction (GOR) to formic acid (FoA) via calcination of a Zn-based zeolitic imidazole framework (ZIF) functionalized with ethylenediamine and doped with Ni. The structure, morphology, and electrochemical performance of the catalysts towards the anodic GOR to FoA coupled with the cathodic hydrogen evolution reaction (HER) are subsequently studied. Chronopotentiometry tests with 0.1 M of glucose show a conversion of 94 % at 250 mA in only 70 min, with a Faradaic efficiency (FE) of 91 % toward the production of FoA. Meanwhile, at the cathode, the HER FE is close to 98 %.