Surface Modification of Carbon NanotubeNetworked Films with Au Nanoclusters forEnhancedNO2Gas Sensing Applications

[摘要] Multiwalled carbon nanotube (MWCNT) films have been deposited by using plasma-enhanced chemical vapor deposition (PECVD) system onto alumina substrates, provided with 6 nm thick cobalt (Co) growth catalyst for remarkably improvedNO2gas sensing, at working temperature in the range of 100–250∘C. Functionalization of the MWCNTs with nanoclusters of gold (Au) sputtering has been performed to modify the surface of carbon nanotube networked films for enhanced and specificNO2gas detection up to sub-ppm level. It is demonstrated that theNO2gas sensitivity of the MWCNT-based sensors depends on Au-loading used as surface-catalyst. The gas response of MWCNT-based chemiresistor is attributed top-typeconductivity in the Au-modified semiconducting MWCNTs with a very good short-term repeatability and faster recovery. The sensor temperature of maximumNO2sensitivity of the Au-functionalized MWCNTs is found to decrease with increasing Au-loading on their surface, and continuous gas monitoring at ppb level ofNO2is effectively performed with Au-modified MWCNT chemiresistors.

[学科分类] 自动化工程