P doped NiCoZn LDH growth on nickel foam as an highly efficient bifunctional electrocatalyst for Overall Urea-Water Electrolysis

Water electrolysis is one of the important methods for hydrogen production, but the oxygen evolution reaction (OER) on the anode has a higher theoretical potential. Using urea oxidation reaction (UOR) instead of OER has been an energy-saving method because it has a lower theoretical potential and also can reduce pollution. In this paper, NiCoZn LDH/NF, P–NiCoZn LDH/NF-X (X is the atom ratio of P) = 10%, 15%, 20%) were synthesized through typically hydrothermal and calcination methods. P–NiCoZn LDH/NF-15% was demonstrated to be abifunctional electrocatalyst towards HER and UOR. When P–NiCoZn LDH/NF-15% is used as the anode and cathode for urea-water electrolysis,it shows that when the current density is 100 mA cm−2, the voltage is 1.479 V for urea-water electrolysis, which is much better than that of IrO2/NF||Pt/C/NF (1.698 V). Thus, P–NiCoZn LDH/NF-15% is expected to replace precious metals for practical applications.