Electropolymerization of Methylene Blue on Carbon Ionic Liquid Electrode and Its Electrocatalysis to 3,4‐Dihydroxybenzoic Acid

Abstract

AbstractIn this paper an ionic liquid modified carbon paste electrode (CILE) was prepared and methylene blue (MB) was electropolymerized on the CILE by using the cyclic voltammetric technique in the potential range from −1.0 V to 0.8 V (vs. SCE). A stable polymer film was obtained and exhibited a pair of redox peaks. The morphology and characteristics of poly(methylene blue) (PMB) film was studied by the techniques such as scanning electron microscopy and electrochemical impedance spectroscopy. This PMB modified CILE (PMB/CILE) showed excellent electrocatalytic response to 3,4‐dihydroxybenzoic acid with the increase of the electrochemical responses. The oxidation peak current had a linear relationship with 3,4‐dihydroxybenzoic acid concentration in the range of 5.0 × 10−4 ∼ 3.0 × 10−2 mol L−1 and the detection limit was 1.72 × 10−4 Mol L−1 (3 σ).