ABSTRACT
Developing cost-effective electrocatalysts for water electrolysis is a promising strategy to enhance conversion and storage efficiency of sustainable energy. Transition metal oxides have been considered as alternative oxygen evolution reaction (OER) catalysts to replace noble metal-based catalysts. Here, we report a series of Fe-doped NiCo2O4 (NCO) nanowires with different Fe-doped concentrations, synthesized by a facile solvothermal and calcinations process, as high-efficiency electrocatalysts for OER. Due to abundant catalytically active sites, high-charge transport capability and specific surface area, these as-obtained NCO nanowires exhibit low overpotential and small Tafel slope. Specifically, NCO-0.1 shows the outstanding OER performance with a low overpotential of 297 mV at a current density of 10 mA cm-2 and a small Tafel slope of about 68 mV dec-1 in 1.0 M KOH. This study offers a promising electrocatalyst for the OER in water splitting.
ABSTRACT
As one of the promising clean and renewable technologies, water splitting has been a hot topic, especially the half-reaction of oxygen evolution reaction (OER) due to its sluggish and complex kinetics. Hence, Fe-doped NiCo2 O4 nanobelts were designed and prepared as catalysts toward OER. By increasing the Fe amount, the catalytic performances of the as-synthesized products went up and then decreased. Profiting from the synergistic effect between Fe atom and NiCo2 O4 , all the Fe-NiCo2 O4 catalysts exhibited superior catalytic activities to the corresponding NiCo2 O4 . In addition, the characteristic nanobelt architecture facilitates the conduction of electrons and the exposure of active sites. With the optimal Fe content, the 9.1 % Fe-NiCo2 O4 yielded the smallest overpotential and Tafel slope among the catalysts, distinctly lower than that of RuO2 .