Multi–walled Carbon Nanotubes Modified Stainless Steel Fiber Felt Supported on Cobalt Electrode for N2H4 Electrooxidation in Alkaline Solution

A multi-walled carbon nanotubes (MWCNTs) modified stainless steel fiber felt (SSFF) supported on cobalt (Co/MWCNTs@SSFF) electrode is synthesized through a simple synthetic strategy that involves a binder-free dipping/drying step to form a MWCNTs@SSFF substrate and a subsequent potentiostatic electrodeposition of Co. The N2H4 electrooxidation reaction on the Co/MWCNTs@SSFF electrode occurs through direct and indirect electrooxidation pathways. The Co/MWCNTs@SSFF electrode achieves a N2H4 electrooxidation peak current density of 97.1 mA cm-2 in 1 M KOH with 0.1 M N2H4, and this current density is far greater than that of a Co/SSFF electrode (29.7 mA cm-2). In comparison with the Co/SSFF electrode, the Co/MWCNTs@SSFF electrode has a larger electrochemical active surface area (ECSA) as well as a lower activation energy (Ea) for N2H4 electrooxidation. The Co/MWCNTs@SSFF electrode exhibits good electrocatalytic properties due to the macroporous structure of the SSFF substrate, porous structure of the Co nanospheres and enhanced ECSA resulting from the MWCNTs modification.