Flexible Electrochemical Sensor for Hydrogen Peroxide Detection by Employing WO3/g-C3N4 Nanostructures

Abstract

This paper describes the fabrication of WO3/g-C3N4 and use of a flexible carbon cloth (CC)-based nonenzymatic detection of hydrogen peroxide (H2O2). The WO3/g-C3N4 was prepared using a hydrothermal method and characterized using various techniques such as field emission scanning electron microscopy (FESEM), powder X-ray diffraction (PXRD), Fourier transform Infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and Brunauer–Emmett–Teller (BET) analysis. Further, the electrodes were fabricated using CC as a flexible and conductive support and was modified with different samples of WO3/g-C3N4 nanostructures (1-WO3/g-C3N4 and 2-WO3/g-C3N4). The electrochemical investigations revealed that the 1-WO3/g-C3N4/CC, and 2-WO3/g-C3N4/CC modified electrodes have strong electrocatalytic activity than WO3 towards the detection of H2O2, which can be attributed to the surface properties, conductivity and resultant interactions of WO3 and g-C3N4 in WO3/g-C3N4. Furthermore, the 1-WO3/g-C3N4/CC, and 2-WO3/g-C3N4/CC demonstrated a sensitivity of 78 μA mM−1 cm−2 and 59 μA mM−1 cm−2, respectively, and were used to measure the concentration of H2O2 in the range of 0.003–0.03 mM. In addition, the LOD of the 1-WO3/g-C3N4/CC, and 2-WO3/g-C3N4/CC was estimated for the sensor as 2.07 μM and 2.53 μM, respectively. These findings suggest that the WO3/g-C3N4 with high conductivity and stability has a promising future in the development of electrochemical sensors.