Tailoring Built‐In Electric Field and Superhydrophilic–Superaerophobic Surface of Fe‐Doped NiTe/NiSe ₂ Heterojunction for Efficient Electrocatalytic Urea Oxidation

ABSTRACT 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.