NiCo Nanoneedles on 3D Carbon Nanotubes/Carbon Foam Electrode as an Efficient Bi-Functional Catalyst for Electro-Oxidation of Water and Methanol

In this study, we report a 3D structured carbon foam electrode assembled from a bifunctional NiCo catalyst, carbon nanotubes (CNT), and a monolith 3D structured carbon foam (CF) as a highly active and stable electrode for oxygen evolution reaction (OER) and methanol oxidation reaction (MOR). When the NiCo@CNTs/CF electrode was used as an anode in OER, after the anodization step, the electrode required a small overpotential of 320 mV to reach the current density of 10 mA cm⁻² and demonstrated excellent stability over a long testing time (total 30 h) in 1 M KOH. The as-prepared NiCo@CNTs/CF electrode also exhibited a good performance towards methanol oxidation reaction (MOR) with high current density, 100 mA cm⁻² at 0.6 V vs. Ag/AgCl, and good stability in 1 M KOH plus 0.5 M CH₃OH electrolyte. The NiCo@CNTs/CF catalyst/electrode provides a potential for application as an anode in water electrolysis and direct methanol fuel cells.