Pt and Pd-nanoclusters functionalized carbon nanotubes networked films for sub-ppm gas sensors (original) (raw)

A gas chemiresistor, fabricated onto alumina using multi-walled carbon nanotubes (MWCNTs) networked films grown by radiofrequency plasma enhanced chemical vapor deposition (RF-PECVD) technology, is described for high-performance gas detection, at an operating temperature of 200 • C. Functionalizations of MWCNTs tangled bundle-films with nominally 5-nm thick Pt-and Pd-nanoclusters, prepared by magnetron sputtering, provide higher sensitivity for significantly enhanced gas detection of NO 2 , H 2 S, NH 3 , CO, up to a low limit of sub-ppm level. The measured electrical conductance of the functionalized MWC-NTs upon gas exposures is modulated by charge transfer with p-type semiconducting characteristics. Ptand Pd-nanoclusters functionalized MWCNTs gas sensors exhibited better performances compared to unfunctionalized MWCNTs, making them promising candidates for air-pollutants environmental monitoring. Simple electronic interface for the chemiresistor has been developed with a voltage output of the sensor signal.