2, University of Science and Technology of Korea, Chanwon, Kyeongnam, Korea (the Republic of)
As demands of hydrogen energy become more increased, the development of electrocatalyst, which has high electrochemical activity, long stability and low-cost is inevitable for hydrogen evolution reaction (HER). In this paper, we report easy method to mass-produce nanosized Ni catalyst using late transition metal oxides, CeO2 and La2O3, on carbon support. The Ni_La0.67Ce0.33O1.67/C catalyst was synthesized by co-precipitation and solvo-thermal that are simple methods and can make higher activity and durability catalyst. Ni_La0.67Ce0.33O1.67 play a key role to reduce size of Ni particles and serve to improve the characteristics of the catalyst in a reducing atmosphere by forming solid solution. Ni_La0.67Ce0.33O1.67/C catalyst was recorded the lower overpotential of 124 mV at current density 10 mA/cm2 and higher long-term stability compared to Ni/C catalyst. We suggest that La0.67Ce0.33O1.67 forms a partial alloy with Ni to prevent Ni detaching and acts as a barrier to prohibit Ni migration. We proposed mechanism of Ni catalyst degradation in the HER electrode based on the results of this work.