High-quality zinc oxide (ZnO) nanorod arrays were grown on a silicon dioxide (SiO 2 /Si) substrate via a microwave irradiation-assisted chemical solution method. The SiO 2 /Si substrate was seeded with polyvinyl alcohol–Zn (OH) 2 nanocomposites prior to the complete growth of ZnO nanorods through a chemical solution method. X-ray diffraction, field-emission scanning electron microscope, and photoluminescence results indicated the high quality of the produced ZnO nanorods. The hydrogen (H 2 )-sensing capabilities of the ZnO nanorod arrays were investigated at room temperature (RT), and the sensitivity was 294% in the presence of 1000ppm of H 2 . The sensing measurements for H 2 gas at various temperatures (25–250°C) were repeatable for over 100min. The sensor exhibited a sensitivity of 1100% at 250°C upon exposure to 1000ppm of H 2 . Hysteresis was observed in the sensor at different H 2 concentrations at different temperatures. Moreover, the response times ranged from 60 to 25s over the range of operating temperatures from RT to 250°C.