Novel Bifunctional V<sub>2</sub>O<sub>3</sub> Nanosheets Coupled with N-Doped-Carbon Encapsulated Ni Heterostructure for Enhanced Electrocatalytic Oxidation of Urea-Rich Wastewater
Guangfu Qian, Jinli Chen, Lin Luo, Hao Zhang, Wei Chen, Zhejiang Gao, Shibin Yin, Panagiotis Tsiakaras
Abstract
Developing high performance bifunctional transition metal catalysts would be significantly beneficial for electrocatalytic oxidation of urea-rich wastewater. Herein, we synthesize a V2O3 nanosheet anchored N-doped-carbon encapsulated Ni heterostructure (Ni@C–V2O3/NF) for the reactions of urea oxidation (UOR) and hydrogen evolution (HER). Electrochemical results indicate that it exhibits small potentials of 1.32, 1.39, and 1.43 V for UOR and low overpotentials of 36, 254, and 355 mV for HER at ±10, ± 500 and ±1000 mA cm–2, respectively. It can work at 100 mA cm–2 for over 72 h as cathode and anode electrode without obvious attenuation, suggesting an outstanding durability. The reason for this behavior could be ascribed to the N-doped-carbon coating structure, the synergetic effects between Ni and V2O3, and the nano/micro nanosheets architecture self-supported on nickel foam. This work could provide a promising, inexpensive, and green method for the degradation of urea-rich wastewater and hydrogen production.