Fabrication of Room Temperature NO2 Gas Sensor based on Silver Nanoparticles-Decorated Carbon Nanotubes

Functionalized-single wall carbon nanotubes (F-SWCNTs) were easily and efficiently decorated with Ag Nanoparticles. The sensor device consisted of a film of sensitive material (F-SWCNTs) and (F-SWCNTs/Ag NPs) deposited by drop coating on n-type porous silicon substrate. The two sensors show high sensitivity to NO2 gas at different temperatures. Test results demonstrated that the (F-SWCNTs/Ag NPs) have a better performance than (F-SWCNTs). The F-SWCNTs gas sensor shows high sensitivity (36 %) at RT with response time 11 sec, whereas F-SWCNTs/Ag NPs gas sensor shows better sensitivity (150.5 %) at RT with response time 8 sec. The device shows a very reproducible sensor performance, with high repeatability, full recovery and efficient response. The improvement in the detection of some specific gases (NO2) using Ag-functionalized nanotubes is explained