V2O5-rGO based chemiresistive gas sensor for NO2 detection

Current study displays an actual hydrothermal synthesis of V2O5-rGO composite and further investigates how changes in rGO composition in V2O5-rGO composites affected their NO2 sensing property. The orthorhombic crystal structure is confirmed by XRD and Raman techniques, and the optimum proportion of disorders in the composite as a result of rGO is also confirmed. Porous nanostructure is observed in SEM images. The C, V, and O present in the composite are confirmed by the XPS results, along with a fluctuation in V4+/V5+. The BET technique was used to measure specific surface area (25.91 m2g−1) and pore radius (6.4140 nm). A prominent PL peak confirm presence of oxygen vacancies. At 150 °C, gas sensing for 100 ppm concentration of NO2 gas revealed improved response about 121.85%. The calculated response/ recovery time for sample consisting 10 mg rGO are 39 and 262 s, respectively. Along with response, sample C shows excellent reproducibility and good stability.