In situ formed Cu3P@CuOx as an efficient electrocatalyst for urea electrooxidation

Substitution of the water oxidation reaction with the urea oxidation reaction can lessen the cost of H2 generation while providing a pathway for wastewater treatment. Nevertheless, an efficient and robust catalyst is required to surmount the kinetic limitations of the urea oxidation reaction (UOR). In this regard, we demonstrate a facile process for depositing Cu3P microspheres on the nickel foam. Based on the results of the post-UOR character-ization of Cu3P, it appears that during UOR, Cu3P was subjected to in-situ surface oxidation to yield a Cu3P@CuOx heterostructure containing a catalytically active amorphous layer of CuOx supported in a conducting Cu3P matrix. As a UOR electrocatalyst, Cu3P was even superior to the RuO2, and it generated a current density of 10 and 100 mA cm-2 at 1.37 and 1.4 V, respectively, with a Tafel slope of 29 mV dec-1. Cu3P displayed a turnover frequency of 1.42 x 10-3 s- 1 at 1.4 V, indicating its high intrinsic catalytic activity. The Cu3P also demonstrated good stability at current densities up to 50 mA cm-2.