Synthesis of porous SnO2 hexagon nanosheets loaded with Au nanoparticles for high performance gas sensors

Abstract

Two-dimensional (2D) porous nanostructures with more active areas and less agglomeration represent an alternative option for new generation of gas sensors. In addition, surface functionalization with noble metals is considered as an effective strategy to improve gas sensing properties of metal oxide-based gas sensors. In this work, a novel gas sensing material was synthesized by decorating Au nanoparticles (Au NPs) on very low thickness SnO2 nanosheets (SnO2 NSs) with side length of 100–300nm. Furthermore, the nanosheets are porous with pore diameter of 5–10nm and a high specific surface area (64.2 m2g−1). Due to the well-aligned 2D nanostructures and the incorporation of the interface between Au nanoparticles and SnO2 nanosheets, the gas sensors based on Au-SnO2 nanocomposites show excellent sensitivity and selectivity to ethanol at the operating temperature of 160°C, giving a response of about 70.2–100ppm ethanol, which was about 3 times higher than that of the sensor based on pure SnO2.