Electrochemical Dopamine Detection Using Palladium/Carbon Nano Onion Hybrids

Abstract

In the given study, palladium-decorated carbon nano-onion nanostructures (Pd/CNO) were used as an electrochemical catalyst for detecting dopamine (DA). The physicochemical properties of the Pd/SO3H/CNO-based catalysts were studied by transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) methods. Pd/SO3H/CNO inks were dropped cast on a glassy carbon electrode (GCE) to prepare the electrochemical DA sensors. The sensor performance was performed using cyclic voltammetry (CV), differential pulse voltammetry (DPV), and electrochemical impedance spectroscopy (EIS). The electroanalytical results indicated a LOD value of 2.44 M and the linear range of the sensors were found to be between 10 and 400 M DA. The enhanced electrocatalytic activity toward DA is attributed to the high active surface area, conductivity of CNO and the high electrocatalytic property of Pd. The results suggest that Pd/SO3H/CNO nanostructures can be used to detect electrochemical DA sensors with high selectivity, sensitivity, and low LOD.