Microwave-Assisted synthesis of CuxFe100-x/Carbon aerogel (x = 0, 30, 50, 70) with enhanced Electrocatalytic activity towards oxygen evolution reaction

A simple and efficient microwave-assisted synthesis route was adopted for carbon aerogel (CA)-supported Cu and Fe catalysts for OER in alkaline media. Catalysts were characterized physically by ICP-MS, XRD, TEM, XPS, SEM, and EDX and electrochemically by CV, chronoamperometry, and EIS. The catalyst having the composition of Cu30Fe70/CA showed excellent activity towards OER with low overpotential (345 mV) and Tafel slope (92.5 mV dec−1). Diffusion coefficient (D° = 2.1 × 10−8 cm2 s−1), mass transport coefficient (mT = 2.8 × 10−4 cm s−1), heterogeneous rate constant (k° = 5.7 × 10−4 cm s−1), and electrochemically active surface area (0.0167 cm2) were obtained for Cu30Fe70/CA modified glassy carbon electrode. CV response in the non-faradic region showed that Cdl and electrochemical surface area (ECSA) of Cu30Fe70/CA increased ∼ 34 times compared to Fe/CA. This work suggests that adding up an optimum amount of Cu to the Fe/CA nanocomposite offers a cost-effective and efficient electrocatalyst for OER.