Enhanced methane sensing performance of NiO decorated In2O3 nanospheres composites at low temperature

In this paper, In2O3 nanospheres and NiO nanoparticles decorated In2O3 nanospheres with enhanced methane (CH4) sensing performance were successfully synthesized via a facile solvothermal method and the subsequent calcination process. Diverse characterization technologies such as X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) were employed to identify their compositions, morphologies and nanostructures. The methane sensing performances of the NiO/In2O3 nanocomposites were compared with the pure In2O3, and the results indicated that the decorating of NiO significant enhanced the sensing capability. The response value of the NiO/In2O3 nanocomposites toward 500 ppm CH4 was ∼13.057, which was nearly 10.3 times higher than that of pure In2O3 at 120 °C. In addition, the optimal operating temperature of In2O3 was reduced from 180 °C to 120 °C after decorated by NiO. Meanwhile, the NiO/In2O3 nanocomposites also displayed the excellent selectivity, good repeatability and stability. This research confirmed that the promising application for CH4 detection of the NiO/In2O3 nanocomposites. [Display omitted] •In2O3 nanosphere and NiO/In2O3 composite were synthesized by a facile solvothermal method.•Modification by NiO nanoparticles could improve the gas sensing performance of In2O3 toward CH4.•The improved gas sensing mechanism the NiO/In2O3-based gas sensor was carefully discussed.