Revealing the Adsorption Mechanisms of Nitroxides on Ultrapure, Metallicity-Sorted Carbon Nanotubes

Autor(en)

Georgina Ruiz Soria, Alejandro Perez Paz, Markus Sauer, Duncan John Mowbray, Paolo Lacovig, Matteo Dalmiglio, Silvan Lizzit, Kazuhiro Yanagi, Angel Rubio, Andrea Goldoni, Paola Ayala, Thomas Pichler

Abstrakt

Carbon nanotubes are a natural choice as gas sensor components given their high surface to volume ratio, electronic properties, and capability to mediate chemical reactions. However, a realistic assessment of the interaction of the tube wall and the adsorption processes during gas phase reactions has always been elusive. Making use of ultraclean single-walled carbon nanotubes, we have followed the adsorption kinetics of NO

₂ and found a physisorption mechanism. Additionally, the adsorption reaction directly depends on the metallic character of the samples. Franck-Condon satellites, hitherto undetected in nanotube-NO

_x systems, were resolved in the N 1s X-ray absorption signal, revealing a weak chemisorption, which is intrinsically related to NO dimer molecules. This has allowed us to identify that an additional signal observed in the higher binding energy region of the core level C 1s photoemission signal is due to the Cî-O species of ketene groups formed as reaction byproducts. This has been supported by density functional theory calculations. These results pave the way toward the optimization of nanotube-based sensors with tailored sensitivity and selectivity to different species at room temperature.

Organisation(en)

Elektronische Materialeigenschaften

Externe Organisation(en)

Elettra Sincrotrone Trieste, Tokyo Metropolitan University, University of the Basque Country

Journal

ACS Nano

Band

8

Seiten

1375-1383

Anzahl der Seiten

9

ISSN

1936-0851

DOI

https://doi.org/10.1021/nn405114z

Publikationsdatum

02-2014

Peer-reviewed

Ja

ÖFOS 2012

103020 Oberflächenphysik, 103018 Materialphysik, 103009 Festkörperphysik

Schlagwörter

ASJC Scopus Sachgebiete

Allgemeiner Maschinenbau, Allgemeine Physik und Astronomie, Allgemeine Materialwissenschaften

Link zum Portal

https://ucrisportal.univie.ac.at/de/publications/b9418516-a5a5-4019-bde8-b407483b6ff9