Facile one-pot synthesis of CuO nanosheet for application as electrocatalyst for methanol oxidation

Abstract

Herein, a simple single step procedure for synthesis of CuO nanosheets (CuO-NS) at room temperature is reported. The structural and morphological evaluation proves that material is highly crystalline in nature. The electrocatalytic activity of CuO-NS for CH3OH oxidation was evaluated using cyclic voltammetry, electrochemical impedance spectroscopy, and chronoamperometry methods in 0.5 M NaOH. The prepared catalyst showed comparable performance in terms of electrocatalytic current in comparison with reported electrodes modified with various transition metal-oxides. The electrochemical studies on CuO-NS reveal intriguing methanol electrooxidation properties with current density of 4.24 mA/cm2 and 75% current retention even after 2000 s, demonstrating its stability in methanol oxidation reaction (MOR). The improved activity of the electrocatalyst is due to mesoporosity and high surface area. Reaction kinetics and mechanism for CH3OH oxidation were studied. Double step chronoamperometric technique shows that CH3OH oxidation was irreversible. The results elucidate superior performance of the prepared catalyst for CH3OH oxidation and are notably promising in direct methanol fuel cell applications.