Nafion-coated copper oxide porous hollow structures modified glassy carbon electrode for non-enzymatic detection of H2O2

Abstract

Metal-oxide nano-porous microstructures have shown high electrocatalytic activity toward hydrogen peroxide oxidation. In this paper, we establish the copper oxide (CuO) porous hollow structures via the hydrothermal method using pluronic F-127 as a surfactant. The electrochemical performance involves the oxidation between Cu(I) and Cu(II) at room temperature. For verifying the formation of the desired morphology of CuO porous hollow structures, the scanning electron microscopy, Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction spectroscopy and H2-temperature-programmed reduction (TPR) were applied. The synthesized samples are hollow microstructures which are formed by CuO nanoparticles. The achieved CuO hollow structures exhibit excellent H2O2 detection properties such as a very low detection limit of 141.1 nM, an extremely wide dynamic detection range of 50 nM–70 mM, an outstanding sensitivity of 13.7 µA µM−1 cm−2 and satisfactory stability in alkaline solution. The good tolerance toward interfering species, the satisfactory behaviour in repeatability and reproducibility and favourable stability verified the promising performance of the proposed sensor. The results of the study on sensing low levels of H2O2 concentrations by using a modified glassy carbon electrode as an optimized electrochemical sensor have been reported. The proposed synthesized nanostructures (CuO porous hollow structures) can be used as sensitive H2O2 biosensors. Essential characterizations and measurements have been performed. The constructed sensor shows acceptable electrocatalytic activity for detecting H2O2. High sensitivity, very low LOD, wide dynamic range, excellent tolerance toward interfering agents, favorable stability and satisfactory reproducibility and repeatability of the sensor have made it suitable for practical applications.