NO2 and CO interaction with plasma treated Au-decorated MWCNTs: Detection pathways

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Selective detection of benzene traces at room temperature using metal decorated carbon nanotubes

AbstractHybrid materials consisting of oxygen plasma treated multiwalled carbon nanotubes (MWCNTs) decorated with four different metal nanoparticles can be tailored for the recognition of benzene vapors with high sensitivity and selectivity. The plasma treatment enables cleaning, activating, functionalizing and metal decorating carbon nanotubes in a single step. Metal nanoparticles transfer significant amount of charge upon adsorption of a target molecule, so as to affect electron transport in the nanotube. When combined in a microsensor array operating at room temperature, the use of benzene-sensitive and benzene-insensitive metal-decorated multiwalled carbon nanotubes can provide selective detection of benzene at trace levels (i.e., detection limit below 50 ppb

Gas sensing properties of multiwall carbon nanotubes decorated with rhodium nanoparticles

International audienceIn the present work, multiwalled carbon nanotubes were decorated with rhodium nanoparticles using a colloidal solution in the post-discharge of an RF atmospheric plasma of argon (Ar) or argon/oxygen (Ar:O 2). The properties of these hybrid materials towards the room temperature detection of NO 2 , C 2 H 4 , CO, C 6 H 6 and moisture were investigated and discussed in view of compositional and morphological studies. It was found that the presence of oxygen in the plasma treatment is essential to significantly enhance the gas response of Rh-decorated multiwalled carbon nanotubes and to avoid response saturation even at low gas/vapor concentrations. These desirable effects are attributed to the presence of oxygen during the CNT plasma treatment since oxygenated vacancies act both as active adsorption sites for gases and as anchoring sites for Rh nanoparticles (the presence of Rh nanoclusters is nearly doubled in Ar:O 2 treated samples as compared to Ar treated samples). The oxygen treatment also makes easier the charge transfer between Rh nanoparticles and carbon nanotubes upon gas adsorption. The method for treating and decorating multiwalled carbon nanotubes used here is simple, fast and scalable for producing gas sensitive nanohybrid materials with uniform and well-controlled properties

Gas sensing properties of multiwall carbon nanotubes decorated with rhodium nanoparticles

International audienceIn the present work, multiwalled carbon nanotubes were decorated with rhodium nanoparticles using a colloidal solution in the post-discharge of an RF atmospheric plasma of argon (Ar) or argon/oxygen (Ar:O 2). The properties of these hybrid materials towards the room temperature detection of NO 2 , C 2 H 4 , CO, C 6 H 6 and moisture were investigated and discussed in view of compositional and morphological studies. It was found that the presence of oxygen in the plasma treatment is essential to significantly enhance the gas response of Rh-decorated multiwalled carbon nanotubes and to avoid response saturation even at low gas/vapor concentrations. These desirable effects are attributed to the presence of oxygen during the CNT plasma treatment since oxygenated vacancies act both as active adsorption sites for gases and as anchoring sites for Rh nanoparticles (the presence of Rh nanoclusters is nearly doubled in Ar:O 2 treated samples as compared to Ar treated samples). The oxygen treatment also makes easier the charge transfer between Rh nanoparticles and carbon nanotubes upon gas adsorption. The method for treating and decorating multiwalled carbon nanotubes used here is simple, fast and scalable for producing gas sensitive nanohybrid materials with uniform and well-controlled properties