Synthesis of 3D hierarchical Ag/CuO nanostructures in the presence of l-histidine and their application

Abstract

We report a facile synthesis of 3D hierarchical Ag/CuO nanostructures via the l-histidine-assisted biomimetic hydrothermal method. The XRD pattern of the 3D hierarchical Ag/CuO prepared in the presence of l-histidine only indicated the peaks belonging to Ag and CuO, and thus confirmed the purity of the nanocomposite. The field emission scanning electron microscopy revealed a large surface area of the 3D hierarchical CuO and Ag nanostructures which confirmed the effect of l-histidine on the morphology of the Ag/CuO. The electrochemical properties of the Ag/CuO nanostructured electrode were investigated by cyclic voltammetry, differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy. The modified glassy carbon electrode demonstrated excellent electrochemical activity towards dopamine oxidation compared to the bare GCE. From the DPV results, the estimated limit of detection (S/N = 3) and limit of quantification (S/N = 10) in the linear segment (0.001–80 μM) of dopamine are 0.077 μM and 0.257 μM, respectively. The sensitivity of this linear segment is 4.54 μA μM−1 cm−2.