Ceria–Graphene\nOxide Nanocomposite for Electro-oxidation\nof Urea: An Experimental and Theoretical Investigation

This study explores the potential of ceria–graphene\noxide\n(CeO<sub>2</sub>-GO) nanocomposites as efficient electrocatalysts\nfor urea electro-oxidation (UOR). This work combines experimental\nand theoretical investigations and characterization techniques confirm\nthe successful formation of the CeO<sub>2</sub> embedded on graphene\noxide sheets. UOR activity was found to be dependent on both OH<sup>–</sup> and urea concentrations. The optimal UOR performance\nwas achieved in a 0.1 M urea and 1.0 M KOH solution, as evidenced\nby the low Tafel slope of 60 mV/dec and high turnover frequency (TOF)\nof 1.690 s<sup>–1</sup>. DFT calculations revealed that the\nCeO<sub>2</sub>-GO nanocomposite exhibited strong urea adsorption\ndue to its favorable bond lengths (Ce–O: 2.58 Å, O–H:\n1.77 Å) and high adsorption energy (−1.05 eV). These findings\nrevealed that the CeO<sub>2</sub>-GO nanocomposites are promising\nas efficient and durable electrocatalysts for urea conversion to valuable\nproducts like nitrogen and hydrogen gas, with potential applications\nin clean energy generation and ammonia synthesis.