Pt nanoparticles decorated SnO2 nanoneedles for efficient CO gas sensing applications

Herein, we report the synthesis, characterization, and gas sensing applications of Pt nanoparticles-decorated SnO2 nanoneedles synthesized through a facile hydrothermal process. The synthesized nanoneedles were characterized for their morphological, structural, compositional and sensing properties using different characterization techniques. The morphological and structural characterizations confirmed the synthesis of well crystalline Pt nanoparticles decorated SnO2 nanoneedles with tetragonal rutile crystal phase. X-ray photoelectron spectroscopic analysis (XPS) confirmed the spatial distribution of Pt metal into SnO2 nanoneedles. Further, gas sensor applications of the synthesized nanoneedles were studies at different operating temperatures and concentrations of the CO gas. The detailed CO gas sensing analysis revealed that at an optimized temperature of 250 °C, the sensor exhibited 23.18 gas response with the response and recovery times of 15 s and 14 s, respectively. The long-term stability and the selectivity of the 3.125 at% Pt-decorated SnO2 nanoneedles were also explored. Finally, a plausible gas sensing mechanism was also proposed.