The urea oxidation reaction (UOR) is a pivotal half-reaction for urea-assisted water splitting to produce hydrogen, direct urea fuel cells and electrochemical degradation of urea-containing wastewater. However, the intrinsic sluggish kinetics of the UOR hampers the real application of these urea-based technologies. Therefore, highly efficient electrocatalysts are required to promote the urea oxidation process. During the past several years, great achievements in both catalyst design and mechanism understanding have been made in this research area. This perspective starts with the discussion of the reaction mechanism of the UOR. Afterwards, we propose and discuss five typical strategies for designing efficient UOR electrocatalysts including promoting the *COO desorption step, developing electrocatalysts with high oxidation states, facilitating the generation of catalytically active species, constructing dual active sites, and heterojunction catalysts via featured examples. Lastly, we conclude this perspective by outlining the remaining challenges, and exploring the future opportunities in this emerging field.
In recent decades, economic growth and the growing demand for limited resources have prompted a global search for more environmentally friendly and sustainable raw materials for the production of chemicals, materials, and fuels. Compared with traditional fossil fuel feedstocks, whose upgrading features high temperature, high pressure and sever greenhouse gas footprint, the upgrading of biomass-derived platform molecules with various functional groups are achievable at room temperature and ambient pressure with the emerging electrocatalytic hydrogenation (ECH) technology. The selectivity and conversion rate of ECH can be manipulated by adjusting and optimizing the electrode material and the composition of the electrolyte. This review summarizes the progress made in the ECH of various biomass platform molecules with different functional groups (such as 5-hydroxymethylfurfural, furfural, and levulinic acid) into chemicals and fuels across different electrocatalytic systems. It introduces the two mechanisms of ECH reaction and systematically reviews those on both noble metal electrocatalysts (Pt, Pd, Ag, Ru, etc.) and non-noble metal electrocatalysts (Cu, Pb, Sn, etc.). Finally, the current challenges and unresolved issues for the ECH of biomass-derived platform molecules are presented. This review will provide useful insights and guideline for the rational design of high-performance electrocatalysts for selective ECH of biomass platform molecules.