Phytic acid acts as an “electronic diaphragm” to enhance the UOR activity and stability of NiSe2 at high current density

The NiSe 2 @PA catalyst coated with organic phosphating layer NiSe 2 was constructed on nickel foam (NF) by a two-step method. NiSe 2 @PA provides an extremely low overpotential to trigger OER and UOR processes and performs better than a single NiSe 2 , enabling a design strategy for highly efficient dual-function electrocatalysts . • NiSe 2 @PA electrocatalyst was fabricated via a facile synthesis strategy. • The PA layer is introduced to adjust the electronic structure of Ni. • NiSe 2 @PA has excellent OER and UOR activity at high current density. • NiSe 2 @PA exhibits highly efficient catalytic performance for urine electrolytic. The development of oxygen evolution reaction (OER) and urea oxidation reaction (UOR) catalysts with high activity and stability at large current density is the key to realizing efficient and energy-saving electrolytic hydrogen production and wastewater degradation. Herein, an interfacial coordination assembly scheme is established to complement phytic acid coordination complex on NiSe 2 (NiSe 2 @PA) nanorods arrays to achieve enhanced and sustained UOR electrocatalytic activity and stability at high current densities. Density functional theory (DFT) proved that the modification of PA on the surface of NiSe 2 can manipulate the electronic states of Ni sites, and the in-situ evolution of charge redistribution surface can promote urea adsorption. It is impressive that PA functionalization can imbue a negatively charged catalyst surface, not only improving hydrophobic/gaseous properties, but also weakening *COO adsorption and facilitating CO 2 removal, reducing catalyst poisoning, and enhancing durability. Therefore, NiSe 2 @PA exhibits excellent UOR performance, with an ultra-low potential of 10 mA cm −2 at 1.295 V (vs. RHE), a small Tafel slope (34.97 mV dec −1 ), and strong durability (500 mA cm −2 @ 110 h). It is comparable to the best nickel-based electrocatalysts recorded to date.