Mesoporous cobalto-cobaltic oxide modified glassy carbon electrode for simultaneous detection of hydroquinone and catechol

The Co₃O₄ electro-catalysts with the mesoporous structure were prepared by the sacrificing template method. The chemical composition, structural and morphological characterizations of Co₃O₄ were examined by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption-desorption (BET). The electrochemical properties of the meso-Co₃O₄ were investigated by differential pulse voltammetry (DPV) and cyclic voltammetry (CV) for the simultaneous detection of hydroquinone (HQ) and catechol (CC) in the phosphate buffer media (PBS). Based on the meso-Co₃O₄ modifier electrode, a sensitive electrochemical sensor for phenolic compounds was successfully fabricated. Under optimal conditions, the detection limits of HQ and CC were found to be 0.1 and 0.1 μΜ (S/N = 3), respectively. The outstanding catalytic capability of meso-Co₃O₄ catalysts may be associated with their large surface area provided by mesoporous structure.