Activated Carbon Supported Ni-Co Layered Double Hydroxides Nanowires: An Effective and Low-Cost Electrocatalyst for Ethanol Electro-Oxidation in Alkaline Media

Abstract

Developing nanostructured electrocatalysts by utilizing low-cost, non-noble metals with good activity and stability to replace noble metals such as Pt and Pd has gained significant interest in the area of sustainable energy production technologies. To that effect, we adopted a facile synthesis route to synthesize NiCo-LDH (layered double hydroxides) nanowires with activated carbon (AC) as support using a one-pot hydrothermal synthesis method. The role of AC on the activity of NiCo-LDH catalyst was studied. The activity of the electrocatalysts was characterized using Cyclic Voltammetry (CV), Electrochemical Impedance Spectroscopy (EIS), and Chronoamperometry (CA) techniques. The NiCo-LDH/AC, with Ni:Co molar ratio of 1:2, exhibited a good electrocatalytic activity of 12.5 mA cm−2 at 1.1 V vs SCE (saturated calomel electrode) at a scan rate of 50 mV s−1 and retained a remarkable cyclic stability of 74.4% even after 200 cycles in 0.1 M NaOH and 1 M EtOH. The better electrocatalytic activity of NiCo-LDH/AC catalyst can be ascribed to the presence of extremely active sites and porous structures as well as a good electron transfer conductivity of AC. The facile synthesis of NiCo-LDH/AC and its attractive performance highlights its potential application as an anodic electrocatalyst in direct ethanol fuel cells (DEFCs).