Enhanced H2S gas-sensing properties of Pt-functionalized In2Ge2O7 nanowires

In2Ge2O7 one-dimensional (1D) nanostructures were synthesized using an evaporation technique. The morphology, crystal structure, and sensing properties of the In2Ge2O7 nanostructures functionalized with Pt to H2S gas at 100 ∘C were examined. The diameters and lengths of the 1D nanostructures were a few tens 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 In2Ge2O7 nanowires. Gas sensors fabricated from the multiple networked In2Ge2O7 nanowires functionalized with Pt exhibited enhanced electrical responses to H2S gas compared to the uncoated In2Ge2O7 nanowires. The responses of the nanowires were improved 240, 234, and 225 fold at H2S concentrations of 10, 25, and 50 ppm, respectively. The enhanced electrical response of the Pt-functionalized In2Ge2O7 nanowire sensor to H2S gas can be attributed to a combination of the spillover effect and the enhanced chemisorption, as well as the dissociation of the gas.