TY - JOUR
T1 - Workfunction of purified and oxidised carbon nanotubes
AU - Ago, H.
AU - Kugler, Th
AU - Cacialli, F.
AU - Petritsch, K.
AU - Friend, R. H.
AU - Salaneck, W. R.
AU - Ono, Y.
AU - Yamabe, T.
AU - Tanaka, K.
N1 - Funding Information:
Acknowledgments - This work was supportedb y Engineering and PhysicalS ciencesR esearchC ouncil (EPSRC),a Grant-in-Aid for ScientificR esearcohn Priority Area “CarbonA lloy” from the Ministry of EducationS, cience,a nd ulture of Japan,a nd by the Japan Society for the Promotion of Science( JSPS-RFTF 96poO206). HA acknowledgetsh e JSPS ResearchF ellowship for Young Scientists. FC acknowledgesth e Royal Society for the awardo f a UniversityR esearchF ellowship.
PY - 1999/6/24
Y1 - 1999/6/24
N2 - We report for the first time the ultraviolet photoelectron spectroscopy (UPS) of purified multi-wall carbon nanotubes. Purification was carried out by successive sonication, centrifuge, sedimentation, and filtration processes of nanotubes-water solution dispersed by the non-ionic surfactant. Purified nanotubes showed the workfunction of 4.3 eV, very close to that of graphite (4.4 eV). It was found that purified nanotubes possess a finite density of states (DOS) at Fermi energy (EF), suggesting the existence of metallic nanotubes as predicted theoretically. The oxygen-plasma treatment which opens the end-cap and generates defects in the outer layers increased the workfunction dramatically up to 4.8 eV and removed the DOS at EF, indicating a new way to modify the electronic properties of nanotubes.
AB - We report for the first time the ultraviolet photoelectron spectroscopy (UPS) of purified multi-wall carbon nanotubes. Purification was carried out by successive sonication, centrifuge, sedimentation, and filtration processes of nanotubes-water solution dispersed by the non-ionic surfactant. Purified nanotubes showed the workfunction of 4.3 eV, very close to that of graphite (4.4 eV). It was found that purified nanotubes possess a finite density of states (DOS) at Fermi energy (EF), suggesting the existence of metallic nanotubes as predicted theoretically. The oxygen-plasma treatment which opens the end-cap and generates defects in the outer layers increased the workfunction dramatically up to 4.8 eV and removed the DOS at EF, indicating a new way to modify the electronic properties of nanotubes.
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U2 - 10.1016/S0379-6779(98)01062-5
DO - 10.1016/S0379-6779(98)01062-5
M3 - Conference article
AN - SCOPUS:0033138028
SN - 0379-6779
VL - 103
SP - 2494
EP - 2495
JO - Synthetic Metals
JF - Synthetic Metals
IS - 1-3
T2 - Proceedings of the 1998 International Conference on Science and Technology of Synthetic Metals (ICSM-98)
Y2 - 12 July 1998 through 18 July 1998
ER -