Abstract
In this paper, we demonstrate and compare the synthesis of copper (Cu) and copper(I) oxide on Cu (Cu/Cu2O) nanoparticles via thermal decomposition method using a combination of oleic acid and oleylamine and oleic acid alone. Using a combination of oleic acid and oleylamine, involves a single nucleation step and control in growth of nanoparticles produces high monodispersity in shape and protects the copper nanoparticles against oxidation. X-ray diffraction (XRD) confirms the formation of single phase Cu only and X-ray photoelectron spectroscopy (XPS) evidences the formation of Cu without any formation of oxides on surfaces for over a long period of time with good stability. In view of interest in electrochemical sensors, we explore the fabrication of a novel and highly sensitive electrode and compare the electrochemical current responses for simultaneous determination of paracetamol and dopamine using Cu/Cu2O nanoparticles stabilized by oleic acid alone and Cu nanoparticles obtained from a combination of oleic acid and oleylamine. Interestingly, we observe that Cu/Cu2O nanoparticles stabilized by oleic acid alone exhibit excellent electrochemical enhancement in the peak current response towards simultaneous determination of paracetamol and dopamine with an increase in peak-peak separation of 239mV. Differential pulse voltammetry (DPV) studies show a linear response to dopamine within the concentration from 0.02μM to 0.159μM with a detection limit of 3.27nM (S/N=3).
Schematic representation of Cu/Cu2O-OA/MWCNTs/GC and Cu-OA-OM/MWCNTs/GC modified electrode in the presence of paracetamol and dopamine simultaneously. [Display omitted]
•Compare the structural and electrochemical properties of Cu and Cu/Cu2O nanoparticles•We examine the modified electrode for simultaneous determination of DA and PA.•Cu/Cu2O on MWCNTs modified electrode shows excellent electrochemical sensor.