Structural and morphological tuning of Cu-based metal oxide nanoparticles by a facile chemical method and highly electrochemical sensing of sulphite
Velayutham Sudha, Govindhasamy Murugadoss, Rangasamy Thangamuthu
Abstract
Abstract A facile one-step chemical method is introduced for the successful synthesis of Cu 2 O, CuO and CuNa 2 (OH) 4 crystal structures and their electrochemical properties were also investigated. X-ray diffraction studies revealed that these copper-based oxide nanoparticles display different crystal structures such as cubic (Cu 2 O), monoclinic (CuO) and orthorhombic [CuNa 2 (OH) 4 ]. The microstructural information of nanoparticles was investigated by transmission electron microscopy. It shows attractive morphologies of different orientation such as rod like structure, nanobeads and well-aligned uniform nanorod for Cu 2 O, CuO and CuNa 2 (OH) 4 , respectively. Electrochemical sensing of sulphite (SO 3 2− ) on these three copper-based oxide modified electrodes was investigated. Among the three different crystal structures, CuO shows promising electrocatalytic activity towards oxidation of sulphite. A linear variation in peak current was obtained for SO 3 2− oxidation from 0.2 to 15 mM under the optimum experimental condition. The sensitivity and detection limit were in the order of 48.5 µA cm −2 mM −1 and 1.8 µM, respectively. Finally, practical utility of CuO modified electrode was demonstrated for the estimation of sulphite in commercial wine samples.