Amorphous nickel tungstate nanocatalyst boosts urea electrooxidation

Urea oxidation reaction (UOR) is an important reaction for achieving a sustainable and clean energy conversion. The reaction rates of UOR on the commonly used Ni-based electrocatalysts, however, are still limited. In this study, an amorphous NiWO₄ nanomaterial synthesized via a facile chemical co-precipitation method is developed as a novel and efficient catalyst for UOR. Impressively, the maximum current density of the prepared amorphous NiWO₄ is almost two orders of magnitude higher than that of the crystalline counterpart. The superior activity is attributed to not only the enrichment of electrochemically active sites, but also the more suitable binding energies toward urea reactant and CO₂ product on the amorphous NiWO₄ as revealed by in situ infrared spectroscopy and theoretical calculations. This work opens up new insights into the development of cost-effective catalysts as well as indicates catalyst phase engineering as a promising strategy for enhancing the UOR performance. © 2023 Elsevier B.V.