Synthesis of SnO2 Nanowires on Quartz and Silicon Substrates for Gas Sensors

• Published in: Journal of inorganic and organometallic polymers and materials 2020-09, Vol.30 (9), p.3294-3304
• Main Authors: Wafaa Khalid, Khalef, Ali Abadi, Aljubouri, Abdulqader Dawood, Faisal
• Format: Article
• Language: English
• Subjects: Aspect ratio; Atomic force microscopy; Chemical vapor deposition; Chemistry; Chemistry and Materials Science; Direct current; Energy gap; Ethanol; Gas sensors; Inorganic Chemistry; Morphology; Nanomaterials; Nanoparticles; Nanowires; Organic Chemistry; Polymer Sciences; Quartz; Room temperature; Scanning electron microscopy; Silicon substrates; Tin dioxide; Tin oxides; X-ray diffraction
• ISSN: 1574-1443; 1574-1451
• DOI: 10.1007/s10904-020-01617-3

Tin oxide nanowires (SnO 2 NWs) were grown on quartz and silicon substrates via a modified chemical vapor deposition (CVD). Film of gold nanoparticle deposited on both types of substrates using the direct current DC-sputtering technique. The structure and morphology of the produced material were characterized by using atomic force microscopy, X-ray diffraction (XRD), scanning electron microscope (SEM) and ultraviolet–visible (UV–Vis) techniques. The XRD and SEM analysis confirmed the formation of tetragonal SnO 2 NWs with a wire length of 10–20 μm and a diameter of 40–100 nm. The UV–Vis spectrum shows a strong absorption peak in the UV and others in the visible regions. The bandgap was calculated for SnO 2 NWs grown on a quartz substrate within the value of 3.2 eV. It is slightly lower than the bandgap value of bulk. The successfully synthesized SnO 2 NWs via CVD with a large aspect ratio in the range of 250–200 was proved to be quite promising nanomaterials to use for sensor fabrication towards ethanol gas at room temperature. The high sensitivity of 2.7 at an ethanol gas concentration of 500 parts per million (ppm) was achieved. The proposed sensing mechanism of SnO 2 NWs towards ethanol gas was also discussed.