TY - JOUR
T1 - Optically polarized 129Xe NMR investigation of carbon nanotubes
AU - Clewett, Catherine F.M.
AU - Morgan, Steven W.
AU - Saam, Brian
AU - Pietraß, Tanja
PY - 2008/12/1
Y1 - 2008/12/1
N2 - We demonstrate the utility of optically polarized 129Xe NMR in a convection cell for measuring the surface properties of materials. In particular, we show adsorption of xenon gas on oxidatively purified single- and multiwalled carbon nanotubes. The interaction between xenon and multiwalled nanotubes produced by chemical vapor deposition was stronger than that of single- or multiwalled nanotubes produced by carbon arc discharge. Xenon was observed in gas, liquid, and adsorbed phases. The large polarization and moderate pressures of xenon (∼0.2 MPa) allowed resolution of multiple lines in both the gas and condensed phases of xenon in contact with carbon nanotubes. Xe gas exchanges with physisorbed xenon in two different environments. Xe adsorbs preferentially on defects, but if the number of defects is not sufficient, it will also adsorb on surface and interstitial sites. Penetration of Xe in the tube interior was not observed.
AB - We demonstrate the utility of optically polarized 129Xe NMR in a convection cell for measuring the surface properties of materials. In particular, we show adsorption of xenon gas on oxidatively purified single- and multiwalled carbon nanotubes. The interaction between xenon and multiwalled nanotubes produced by chemical vapor deposition was stronger than that of single- or multiwalled nanotubes produced by carbon arc discharge. Xenon was observed in gas, liquid, and adsorbed phases. The large polarization and moderate pressures of xenon (∼0.2 MPa) allowed resolution of multiple lines in both the gas and condensed phases of xenon in contact with carbon nanotubes. Xe gas exchanges with physisorbed xenon in two different environments. Xe adsorbs preferentially on defects, but if the number of defects is not sufficient, it will also adsorb on surface and interstitial sites. Penetration of Xe in the tube interior was not observed.
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U2 - 10.1103/PhysRevB.78.235402
DO - 10.1103/PhysRevB.78.235402
M3 - Article
AN - SCOPUS:57749121432
SN - 1098-0121
VL - 78
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
IS - 23
M1 - 235402
ER -