Details

Autor(en) / Beteiligte

• Allsop, Thomas
• Arif, Raz
• Neal, Ron
• Kalli, Kyriacos
• Kundrát, Vojtěch
• Rozhin, Aleksey
• Culverhouse, Phil
• Webb, David J

Titel

Photonic gas sensors exploiting directly the optical properties of hybrid carbon nanotube localized surface plasmon structures

Ist Teil von

• Light, science & applications, 2016-02, Vol.5 (2), p.e16036-e16036

Ort / Verlag

London: Nature Publishing Group UK

Erscheinungsjahr

2016

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• We investigate the modification of the optical properties of carbon nanotubes (CNTs) resulting from a chemical reaction triggered by the presence of a specific compound (gaseous carbon dioxide (CO 2 )) and show this mechanism has important consequences for chemical sensing. CNTs have attracted significant research interest because they can be functionalized for a particular chemical, yielding a specific physical response which suggests many potential applications in the fields of nanotechnology and sensing. So far, however, utilizing their optical properties for this purpose has proven to be challenging. We demonstrate the use of localized surface plasmons generated on a nanostructured thin film, resembling a large array of nano-wires, to detect changes in the optical properties of the CNTs. Chemical selectivity is demonstrated using CO 2 in gaseous form at room temperature. The demonstrated methodology results additionally in a new, electrically passive, optical sensing configuration that opens up the possibilities of using CNTs as sensors in hazardous/explosive environments. Plasmonics: photonic gas sensor An all-optical gas sensor based on carbon nanotubes on a plasmonic structured fibre provides sensitive detection of carbon dioxide gas. Thomas Allsop and co-workers say that the approach offers initial detection limits as low as 150 parts per million at a pressure of one atmosphere. The device consists of a milled optical fibre whose flat surface is coated with thin layers of germanium, silicon dioxide and platinum that are patterned by ultraviolet light to form a surface relief grating. This grating features a plasmonic resonance that is sensitive to changes in the optical properties of the carbon nanotubes on its surface induced by exposure to carbon dioxide. The presence of carbon dioxide manifests itself as a small shift in the plasmon resonance wavelength, which increases with increasing carbon dioxide concentration.