| 초록 |
Developing earth-abundant, highly efficient and durable electrocatalysts for alkaline water oxidation with considerable surface area, high electrical conductivity, excellent catalytic properties and low fabrication cost is extremely desirable. Herein, the three-dimensional (3D) hierarchical core-shell nanohybrids based on the few layer amorphous Co-Fe-Bi nanosheets directly grown on NiCo2O4 nanowires supported on Ni foam (Co-Fe-Bi/NiCo2O4/NF) are facilely fabricated as the highly efficient and durable electrocatalysts for alkaline water electrolysis. Benefitting from hierarchical core-shell nanohybrid design with novel materials chemistry, large surface area, fast electron transport, and open-channels for accelerating effective gas release, the resulting self-supported Co-Fe-Bi/NiCo2O4/NF nanohybrid electrocatalysts shows outstanding electrocatalytic activity with overpotential of 227 mV at 10 mA/cm2, Tafel slope of 45 mV dec-1, excellent durability over 40 h, and capable of delivering current density of 200 mA/cm2 at an overpotential of ~ 350 mV in an alkaline medium. Such an excellent electrocatalytic performance of Co-Fe-Bi/NiCo2O4/NF nanohybrids demonstrates the prominence of design and development of core-shell nanohybrids for large-scale practical applications in the multitude of energy-conversion devices. |
