Boosted urea electro-oxidation over Ni3N-based nanocomposite via systematic regulation tactic

Abstract

Exploiting high-efficiency Ni-based materials for electrocatalytic urea oxidation reaction (UOR) is critical for urea-related technologies. The catalytic site density, intrinsic activity, charge transfer, and mass diffusion determine overall electrocatalytic efficiency. Simultaneous modulation over the above four factors promises advanced electrocatalysis, yet challenging. Herein we propose a systematic regulation tactic over composition and geometric structure, constructing a nanocomposite comprising Mn doped Ni3N nanoparticles anchored on reduced graphene oxide (rGO/Mn-Ni3N), achieving elegant integration of four design principles into one, thereby eminently boosting UOR. Particularly, Mn doping in Ni3N can modulate electronic state to induce intrinsic activity regulation. Combining metallic Mn-Ni3N with rGO to engineer hierarchical architecture not only promotes charge transfer, but also enriches active site population. Intriguingly, improved hydrophilicity could impart better electrolyte penetration and gas escape. Consequently, such system-optimized rGO/Mn-Ni3N demonstrates state-of-the-art-level UOR electrocatalysis. This work offers a novel paradigm to create advanced catalysts via systematic and integrated modulation.