Tailoring Built-In Electric Field and Superhydrophilic–Superaerophobic Surface of Fe-Doped NiTe/NiSe2 Heterojunction for Efficient Electrocatalytic Urea Oxidation

Electrocatalytic urea oxidation reaction (UOR) holds great promise in green energy conversion and pollutant degradation with low energy-consumption. Herein, Fe-NiTe/NiSe 2 nanosheets array with super-hydrophilic/aerophobic surface and enhanced built-in electric field is constructed. The surface hydrophilic/aerophobic properties enabling rapid bubble nucleation and efficient detachment, liberating covered active sites, thus improving the surface adsorption kinetics of urea molecular and OH − . Moreover, Fe incorporation accelerates charge transfer and modulates the built-in electric field at the NiTe/NiSe 2 heterojunction interface. This reduces the surface reconstruction potential and optimizes the occupancy of hybrid anti-bonding (d-δ)* orbitals, leading to the formation of electron-rich region (Fe-NiTe) and electron-deficient region (Fe-NiSe 2 ), which preferentially adsorbs the electron-withdrawing (C═O) and electron-donating (─NH 2 ) groups of urea, respectively, thereby optimizing the adsorption energy of urea molecules. Therefore, the Fe-NiTe/NiSe 2 heterojunction exhibits excellent alkaline UOR performance, requiring only 1.447 V RHE to deliver a current density of 100 mA cm −2 , which it can maintain for over 90 h. The Fe-NiTe/NiSe 2 (+) ∥ Pt/C (-) urea electrolyzer can maintain stable for 150 h at 100 mA cm −2 . This work offers a macro- and microscopic coupling engineering strategy to address the surface and intrinsic properties for alkaline UOR, holding significant practical value for advancing energy-efficient hydrogen production and wastewater treatment.