Abstract：NiCo alloy possesses bi-functional electrocatalytic properties which could significantly improve the efficiency for water splitting and reduce the cost as well. In this work, hierarchical NiCo alloy nanosheets were synthesized on a corrosion-resistant Ti foil by electrodeposition method through adjusting deposition current density and time. Based on parameters optimization, the results indicated that uniform nanosheet-nanoparticle hierarchical structures were able to be obtained within 5 minutes with the current density of 75mAcm-2. XRD and high resolution TEM characterization confirmed the formation of bifunctional NiCo alloy in the hierarchical nanostructures and Ni/Co atomic ratio varied with the reaction time. Benefiting from the increased surface active sites, nanosheet-nanoparticle hierarchical structure exhibited excellent electrocatalytical properties compared with the other samples. Under alkaline conditions, the hierarchical structure exhibited HER and OER overpotentials of 517mV and 392mV, respectively, at 10mAcm-2. The hierarchical structure obtained in this work is expected to be a novel electrocatalyst for electrocatalytical water splitting which may replace noble metal catalysts.
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2019, Vol. 26 