The enhanced ethanol sensing properties of multi-walled carbon nanotubes/SnO_2 core/shell nanostructures

摘要

Multi-walled carbon nanotubes/SnO_2 (CNT/SnO_2) core/shell nanostructures were synthesized by a simple wet-chemical method. The thickness of the SnO_2 shell was about 10 nm and the diameters of the SnO_2 particles were 2-8 nm. Sensors based on the core/shell heterostructures exhibited enhanced ethanol sensing properties. The sensitivity to 50 ppm ethanol was up to 24.5, and the response time and recovery time were about 1 and 10 s, respectively. In addition, the fluctuation of the sensitivity was less than + -3 percent on remeasurement after 3 months. These results indicate that the core/shell nanostructures are potentially new sensing materials for fabricating gas sensors.