Preparation and Electrochemical Properties of Co₅Ni₁O_x/Carbon ClothBifunction Electrocatalyst for Water Electrolysis

The electrocatalyst Co₅Ni₁O_x/carbon cloth (CC) was synthesized by hydrothermal method. The microstructure, electrocatalytic performance of oxygen evolution reaction/hydrogen evolution reaction and water electrolysis property were studied, and compared with those of Co₆O_x/CC, Ni₆O_x/CC and commercial RuO₂ and Pt/C electrocatalysts. The results show that Co₅Ni₁O_x nanorods in Co₅Ni₁O_x/CC sample anchored on CC surface. When the current density was 10 mA·cm^-2, the overpotential of oxygen evolution reaction of Co₅Ni₁O_x/CC sample was 289 mV, significantly lower than 342,405,422 mV of Co₆O_x/CC sample, Ni₆O_x/CC sample and RuO₂ electrocatalyst; the overpotential of hydrogen evolution reaction was 200 mV, lower than 252,364 mV of Co₆O_x/CC sample and Ni₆O_x/CC sample and close to 44 mV of Pt/C electrocatalyst. The voltage of electrolytic cell assembled by Co₅Ni₁O_x/CC sample was 1.69 V, lower than 1.78, 1.85 V of electrolytic cell assembled by Co₆O_x/CC sample and Ni₆O_x/CC sample, respectively, and similar to 1.70 V of electrolytic cell assembled by RuO₂ and Pt/C electrocatalysts as anode and cathode, respectively.