Study on Electrocatalytic Urea Oxidation Performance of Nickel-lanthanum Layered Double Hydroxide

The electrocatalytic urea oxidation reaction (UOR) has garnered extensive attention due to its demonstrated energy-saving and environmental benefits in the treatment of urea-containing wastewater and hydrogen production. However, the construction and development of efficient and stable electrocatalysts remain a research hotspot and challenge. In this study, nickel-lanthanum layered double hydroxide nanomaterials were prepared via a hydrothermal method, exhibiting a hydrangealike structure composed of two-dimensional nanosheets. The research revealed that the doping of lanthanum (La) reduced the crystallinity of the material and modulated the electronic structure of nickel (Ni), resulting in an increase in Ni's electron density. Electrochemical performance tests demonstrated that the catalyst exhibited optimal UOR performance when the molar ratio of Ni to La was 1 ∶ 0.1, achieving a potential of 1.489 V vs. RHE at a current density of 50 mA·cm^-2 with a low Tafel slope of 23.02 mV·dec^-1. Additionally, it displayed excellent stability and an ability to suppress the oxygen evolution reaction. This work provides insights into the modification of electrocatalytic materials through rare earth doping.