Au decorated WO 3 -SnO 2 nanocomposite for enhanced benzene vapors sensing performance

• Published in: Physica scripta Vol. 98; no. 4; p. 45809
• Main Authors: Nihal, Sharma, Rahul, Sharma, Mamta, Goswamy, J K
• Format: Journal Article
• Language: English
• Published: 01.04.2023
• ISSN: 0031-8949; 1402-4896
• DOI: 10.1088/1402-4896/acbfed

Abstract In this present work, we synthesized WO 3 -SnO 2 and Au decorated WO 3 -SnO 2 nanocomposite by hydrothermal method. The optical characterization has been done by UV/Vis spectroscopy to determine the band gap (Eg) of pure and gold (Au) decorated WO 3 -SnO 2 which shows a reduction in Eg value from 3.56 to 3.03 eV after addition of Au in WO 3 -SnO 2 which improves the crystallinity of WO 3 -SnO 2 . Fourier transformed Infra red (FTIR) spectroscopy has been used to confirm the chemical bonding between Au and WO 3 -SnO 2 nanocomposite. The x-ray Diffraction (XRD) technique was used to study the structural aspects of prepared materials which shows the decrease in crystallite size from 8 to 6.7 nm after addition of Au in pure sample. Field Emission Scanning Electron Microscopy (FESEM) has been used to investigate morphological characteristics of as prepared nanocomposite. The doping of Au was further confirmed by Energy-Dispersive x-ray spectroscopy (EDS) technique. The sensing properties have been studied from the I–V measurement of WO 3 -SnO 2 /Au nanocomposite for Benzene. The sensing parameters such as sensitivity (response), operating temperature and response and recovery time were calculated for benzene vapors. The addition of Au in WO 3 -SnO 2 increases its response to 2.7 times for 100 ppm benzene with a reduction in response/recovery time from 18/50 s to 13/29 s. The operating temperature was 300 °C. Further, the material is highly selective for benzene as compared to cyclohexane, toluene and aniline.