Pt nanoparticle decoration on femtosecond laser-irradiated SnO2 nanowires for enhancing C7H8 gas sensing

In this study, we have fabricated a sensitive and selective toluene gas sensor based on SnO2 nanowires (NWs) using the femtosecond (FS) laser irradiation and Pt nanoparticle (NPs) decoration. The effects of different laser parameters, including wavelength, laser pulse energy, hatch distance, and scan speed, are investigated on the gas-sensing properties. The FS laser irradiation-induced embossing surface is found to be a dominant factor in determining the gas-sensing behavior, which provides more oxygen absorption sites, resulting in an increase in the width of the electron depletion layer (EDL) and the sensor response. The Pt decoration on the FS laserirradiated SnO2 NWs developed additional EDL, which further enhances the sensor response. The Pt-decorated and FS laser-irradiated SnO2 NWs gas sensor shows a high selectivity toward C7H8 owing to the catalytic effect of Pt toward toluene, where the sensor response to 50 ppm C7H8 is as high as 53 at 300 degrees C. Based on X-ray photoelectron spectroscopy and transmission electron microscopy analyses, a gas-sensing mechanism of the Ptdecorated and FS laser-irradiated SnO2 NWs gas sensor is proposed. This study highlights a promising combination of Pt decoration and FS laser irradiation for the realization of reliable toluene gas sensors.

Automated summary

In this study, a sensitive and selective toluene gas sensor based on SnO2 nanowires (NWs) was fabricated using FS laser irradiation and Pt nanoparticle (NPs) decoration. The FS laser irradiation-induced embossing surface was found to be dominant in determining the gas-sensing behavior, while Pt decoration on the FS laser-irradiated SnO2 NWs further enhanced the sensor response. The gas sensor showed high selectivity towards C7H8 and exhibited promising potential for reliable toluene gas sensing applications.