Fabrication and CO gas-sensing properties of Pt-functionalized Ga2O3 nanowires

Ga2O3 one-dimensional (1D) nanostructures were synthesized using an evaporation technique. The morphology, crystal structure and enhanced sensing properties of the Ga2O3 nanostructures functionalized with Pt to CO gas at 100 °C were examined. The diameter and lengths of the 1D nanostructures ranged from a few tens to a few hundreds of nanometers and up to a few hundreds of micrometers, respectively. Pt nanoparticles with diameters of a few tens of nanometers were distributed over the Ga2O3 nanowires. Multiple networked gas sensors fabricated from these Pt-functionalized Ga2O3 nanowires exhibited enhanced electrical responses to CO gas. The responses of the nanowires were improved 27.8, 26.1, 22.0 and 16.9 fold at CO concentrations of 10, 25, 50, and 100 ppm, respectively, Compared to the bare Ga2O3 nanowires. The mechanism responsible for the enhanced gas sensing properties of the Pt-functionalized Ga2O3 nanowires is discussed.