Detection of hydrogen peroxide vapor using flexible gas sensor based on SnO2 nanoparticles decorated with multi-walled carbon nanotubes

In this work, a high-sensitive flexible sensor based on the SnO2 nanoparticles decorated with the multi-walled carbon nanotubes (MWCNTs) was fabricated by a simple and cost-effective centrifugation method for hydrogen peroxide vapour (HPV) detection. Morphological, composition, structural, and HPV sensing studies of the film were thoroughly conducted. Scanning electron microscopy (SEM) revealed the presence of MWCNTs in the SnO2 material and energy dispersive x-ray (EDX) elementary analysis determined the actual concentration of carbon elements (24.47 wt%) in the SnO2:MWCNTs material with pronounced peaks of C, O, and Sn. Elemental mapping analysis showed the nearly homogeneous distribution of the elements while x-ray diffraction analysis (XRD) confirmed the diffraction peaks of tin oxide and carbon. The HPV sensing behaviour of the flexible SnO2:MWCNTs sensor was investigated in the temperature range of 25 °C–150 °C towards 1.5–56 ppm HPV under ultraviolet (UV) irradiation. The flexible sensor had a fairly high response (44) to 1.5 ppm of HPV concentration at room temperature (RT). The fabricated SnO2:MWCNTs based sensor was capable of detecting extremely low concentrations of HPV, thus being a potential candidate for use in real environments.