Synthesis of Carbon Nanotubes by Chemical Vapor Deposition and their Application for CO2 and CH4 Detection

In this letter, we demonstrate synthesis of Carbon Nanotubes (CNTs) and also, fabrication and testing of CNTs-based gas sensors. CNTs were synthesized by Floating Catalyst Chemical Vapor Deposition (FC-CVD) at 950 degrees C under methane gas flow rate of 150 Standard Cubic Centimeters per minute (SCCM) on quartz substrate. Then, the electrical resistance of CNTs was measured by exposing the sensor to CO2 and CH4 concentrations operating at room temperature. The sensors were highly responsive to the gaseous molecules. In the same experimental conditions, the recovery of the sensors was different for CO2 and CH4. The fabrication process was relatively simple and did not require special techniques.