Tailor-designed binary Ni–Cu nano dendrites decorated 3D-carbon felts for efficient glycerol electrooxidation

Abstract

Herein, 3D-Carbon Felt (CF) are decorated with nickel–copper (Ni–Cu@CF) bimetallic nanostructures through either sequential or co-electrodeposition tactics. Their catalytic activity towards glycerol electrooxidation is investigated by employing cyclic voltammetry (CV) and linear sweep voltammetry LSV. The morphology and composition of the various Ni–Cu@CF are investigated using X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) together with various electrochemical measurements (e.g., CV, chronoamperometry, LSV). The co-deposition of Ni–Cu shows a dendritic-like structure with higher electrocatalytic activity towards glycerol electrooxidation compared to the monometallic counterparts. Interestingly, the best electrode (NiCu@CF Ni particles as the top layer) prepared by sequential electrodeposition shows 1.6-fold higher glycerol oxidation activity, manifested in oxidation current, compared to Ni-coated CF due to Ni particles covering the surface of dendritic copper uniformly. Thus, the surface concentration of Ni is increased and at the same time a synergistic effect occurs between Ni and Cu by the simple addition of Cu which reinforces the surface concentration of Ni from 3.4 × 10⁻⁸ to 1.1 × 10⁻⁷ mol cm⁻².