Electronic structure engineering of electrocatalyst for efficient urea oxidation reaction

Urea electrolysis is a viable approach to produce hydrogen energy, while the urea oxidation reaction (UOR) presents major obstacles due to its low conversion efficiency and high kinetic barriers. To achieve the full potential of UOR, engineering the electronic structure of UOR electrocatalysts is expected not only to realize high-valence active centers but also to improve the electrical conductivity, thus boosting the overall catalytic efficacies. Furthermore, electronic structure engineering holds promise for facilitating the interface-driven electron transfer, fine-tuning the binding strength of essential reaction intermediates (e.g., NH*, and CO*), and enabling the COO* desorption step in the reaction pathway. In order to construct electronic modulation of electrocatalysts, it is crucial to comprehend how electronic structure engineering impacts UOR activity and what guidelines should be followed. In this review, we begin with an overview of the key differences between water electrolysis and urea electrolysis, then go over the activity parameters used to evaluate the catalytic efficacies that could be expected to help readers to gain a fundamental understanding of this field. This will be followed by outlining the first principles and key parameters of catalyst electronic structure engineering for the benefit of the reader. Furthermore, detailed notes were provided on the potential of electronic structure-engineered catalysts to speed up the UOR kinetics with a focus on interface engineering, doping engineering, defect engineering, phase engineering, and strain engineering. Finally, we discuss the difficulties and opportunities that lie beneath the prospect of developing electrocatalysts for UOR that are both efficient and effective in the future.