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

This paper describes the fabrication of WO 3 / g -C 3 N 4 and use of a flexible carbon cloth (CC)-based nonenzymatic detection of hydrogen peroxide (H 2 O 2 ). The WO 3 / g -C 3 N 4 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 WO 3 / g -C 3 N 4 nanostructures (1-WO 3 / g -C 3 N 4 and 2-WO 3 / g -C 3 N 4 ). The electrochemical investigations revealed that the 1-WO 3 /g-C 3 N 4 /CC, and 2-WO 3 /g-C 3 N 4 /CC modified electrodes have strong electrocatalytic activity than WO 3 towards the detection of H 2 O 2 , which can be attributed to the surface properties, conductivity and resultant interactions of WO 3 and g -C 3 N 4 in WO 3 / g -C 3 N 4. Furthermore, the 1-WO 3 /g-C 3 N 4 /CC, and 2-WO 3 /g-C 3 N 4 /CC demonstrated a sensitivity of 78 μ A mM −1 cm −2 and 59 μ A mM −1 cm −2 , respectively, and were used to measure the concentration of H 2 O 2 in the range of 0.003–0.03 mM. In addition, the LOD of the 1-WO 3 /g-C 3 N 4 /CC, and 2-WO 3 /g-C 3 N 4 /CC was estimated for the sensor as 2.07 μ M and 2.53 μ M, respectively. These findings suggest that the WO 3 / g -C 3 N 4 with high conductivity and stability has a promising future in the development of electrochemical sensors.