화학공학소재연구정보센터
International Journal of Hydrogen Energy, Vol.43, No.29, 12917-12928, 2018
Nickel-cobalt-oxide cathodes for hydrogen production by water electrolysis in acidic and alkaline media
Mixed Ni Co-oxide cathodes of various compositions were fabricated by a thermal decomposition method and used as electrocatalysts for hydrogen production by water electrolysis in acidic and alkaline media. The oxide electrodes were found to be of a semi crystalline structure, yielding the surface morphology characterized by a surface roughness factor going up to 25. Linear potentiodynamic and potentiostatic electrochemical measurements revealed that the Volmer reaction step controlled the kinetics of the hydrogen evolution on all the Ni Co-oxide cathodes, and also on the pure metal Ni electrode (control). The Ni0.2Co0.8-oxide was identified as the best electrode material candidate among the investigated metal oxides, which was linked to the surface-area effect. However, its intrinsic activity was found to be lower than that of pure metallic Ni. Nevertheless, the Ni0.2Co0.8-oxide electrode showed a significantly higher electrocatalytic stability (fouling/deactivation tolerance) in comparison to metallic Ni. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.