Manganese-facilitated dynamic active-site generation on Ni₂P with self-termination of surface reconstruction for urea...

Electrochemical urea oxidation reaction (UOR) suffers from sluggish reaction kinetics due to its complex 6-electron transfer processes combined with conversion of complicated intermediates, severely retarding the overall energy conversion efficiency. Herein, manganese-doped nickel phosphide nanosheets (Mn-Ni₂P) are constructed and employed for driving UOR. Comprehensive analysis deciphers that Mn doping could efficiently accelerate the surface reconstruction of Mn-Ni₂P electrode, generating highly reactive NiOOH-MnOOH heterostructure with local nucleophilic and electrophilic regions. Such unique structure could accelerate the targeted adsorption and activation of C and N atoms, promoting fracture of CN bond in urea. In addition, moderate Mn doping could efficiently enhance the adsorption capacities of urea molecules and some key intermediates, and minish the energy barrier for *CO₂ desorption, accelerating refreshing of the catalyst. Consequently, the Mn-Ni₂P electrode exhibits excellent UOR catalytic activity, achieving an industrial-level current density of 1000 mA cm^-2 at 1.46 V (vs. RHE).