Enhancement of the Electron Spin Resonance of Single-Walled Carbon Nanotubes by Oxygen Removal

dc.citation.firstpage2165
dc.citation.issueNumber3
dc.citation.journalTitleACS Nano
dc.citation.lastpage2173
dc.citation.volumeNumber6
dc.contributor.authorRice, William D.
dc.contributor.authorWeber, Ralph T.
dc.contributor.authorLeonard, Ashley D.
dc.contributor.authorTour, James M.
dc.contributor.authorNikolaev, Pavel
dc.contributor.authorArepalli, Sivaram
dc.contributor.authorBerka, Vladimir
dc.contributor.authorTsai, Ah-Lim
dc.contributor.authorKono, Junichiro
dc.date.accessioned2016-07-08T16:43:04Z
dc.date.available2016-07-08T16:43:04Z
dc.date.issued2012
dc.description.abstractWe have observed a nearly 4-fold increase in the electron spin resonance (ESR) signal from an ensemble of single-walled carbon nanotubes (SWCNTs) due to oxygen desorption. By performing temperature-dependent ESR spectroscopy both before and after thermal annealing, we found that the ESR in SWCNTs can be reversibly altered via the molecular oxygen content in the samples. Independent of the presence of adsorbed oxygen, a Curie law (spin susceptibility ∝ 1/T) is seen from ∼4 to 300 K, indicating that the probed spins are finite-level species. For both the pre-annealed and post-annealed sample conditions, the ESR line width decreased as the temperature was increased, a phenomenon we identify as motional narrowing. From the temperature dependence of the line width, we extracted an estimate of the intertube hopping energy; for both sample conditions, we found this hopping energy to be ∼1.2 meV. Since the spin hopping energy changes only slightly when oxygen is desorbed, we conclude that only the spin susceptibility, not spin transport, is affected by the presence of physisorbed molecular oxygen in SWCNT ensembles. Surprisingly, no line width change is observed when the amount of oxygen in the SWCNT sample is altered, contrary to other carbonaceous systems and certain 1D conducting polymers. We hypothesize that physisorbed molecular oxygen acts as an acceptor (p-type), compensating the donor-like (n-type) defects that are responsible for the ESR signal in bulk SWCNTs.
dc.identifier.citationRice, William D., Weber, Ralph T., Leonard, Ashley D., et al.. "Enhancement of the Electron Spin Resonance of Single-Walled Carbon Nanotubes by Oxygen Removal." <i>ACS Nano,</i> 6, no. 3 (2012) American Chemical Society: 2165-2173. http://dx.doi.org/10.1021/nn204094s.
dc.identifier.doihttp://dx.doi.org/10.1021/nn204094s
dc.identifier.urihttps://hdl.handle.net/1911/90844
dc.language.isoeng
dc.publisherAmerican Chemical Society
dc.rightsThis is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by the American Chemical Society.
dc.subject.keywordelectron spin resonance
dc.subject.keywordoxygen desorption
dc.subject.keywordsingle-walled carbon nanotubes
dc.titleEnhancement of the Electron Spin Resonance of Single-Walled Carbon Nanotubes by Oxygen Removal
dc.typeJournal article
dc.type.dcmiText
dc.type.publicationpost-print
Files
Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
1110.5220v1.pdf
Size:
1.49 MB
Format:
Adobe Portable Document Format
Description: