Alcohol Electrooxidation Study on Carbon Nanotube Supported Monometallic, Pt, Bi, and Ru Catalysts

Abstract

In the present study, carbon nanotube supported Pt (Pt/CNT), Bi (Bi/CNT), and Ru (Ru/CNT) catalysts are prepared via NaBH4 reduction method for ethanol (C2H5OH), ethylene glycol (C2H6O2), and methanol (CH3OH) electrooxidation. The physical characterization of these as-prepared catalysts is performed by X-ray diffraction (XRD). Furthermore, electrochemical measurements are conducted via cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), chronoamperometry (CA), and linear sweep voltammetry (LSV). Pt/CNT catalyst exhibits the highest catalytic activity and stability compared to Bi (Bi/CNT) and Ru (Ru/CNT) catalysts. It is observed that the electrocatalytic activity of Pt/CNT catalyst for ethylene glycol (C2H6O2) oxidation is higher than its electrocatalytic activities for ethanol (C2H5OH) and methanol (CH3OH) oxidation. Maximum current density of C2H6O2 of Pt/CNT catalyst is about 4 and 5.7 times lower than C2H5OH and CH3OH. Furthermore, electrochemical impedance spectroscopy (EIS), chronoamperometry (CA), and linear sweep voltammetry (LSV) results are in good agreement with CV results in terms of stability and electrocatalytic activity of Pt/CNT. The Pt/CNT catalyst is believed to be a promising anode catalyst for the alcohol fuel cells.