Synthesis and Fabrication of ZnO Nanorods on Silicon for Methanol Gas Sensor

Abstract

Zinc Oxide nanorods (ZnO NRs) were successfully synthesized via hydrothermal method. The growth process was conducted with seed layer concentration of 30 mM. The as-synthesized nanostructures were characterized by x-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscope (AFM), and ultraviolet-visible (UV-VIS) spectrophotometer. The analysis results revealed a pure Wurtzite ZnO hexagonal nanostructures with preferred orientation (002) along c-direction. The calculated band gap and crystallite size are 3.2 eV and 53.18 nm respectively. A methanol gas sensor was fabricated based on the annealed ZnO NRs on the silicon substrate. Optimized sensitivity at 250 ppm methanol vapor with fast response and recovery time was achieved. So, ZnO NRs film can serve as a good candidate for a methanol gas sensing device.

Keywords

• hydrothermal
• zno nrs
• methanol gas sensors
• crystallite size