Electronic properties of Cs-intercalated single-walled carbon nanotubes derived from nuclear magnetic resonance

Edy Abou-Hamad (Författare), Christophe Goze-Bac (Författare), Florian Nitze (Författare), Michael Schmid (Författare), Robert Aznar (Författare)

URI http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-45736, URN urn:nbn:se:umu:diva-45736, DOI 10.1088/1367-2630/13/5/053045

Umeå universitet Teknisk-naturvetenskapliga fakulteten (Utgivare)

utgivning

IOP Publishing Ltd and Deutsche Physikalische Gesellschaft, 2011

är del av

New Journal of Physics · ISSN 1367-2630

13, 053045 (1)-(9)

Bidrag, Onlineresurs

Finns online:

http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-45736

web site

ämne

Natural Sciences, Physical Sciences, Naturvetenskap, Fysik, NATURAL SCIENCES, Physics, NATURVETENSKAP, Fysik, fysik, Physics, Carbon nanotubes, NMR, Intercalation, Cesium, Electronic properties

Fler detaljer Referera

Sammanfattning

We report on the electronic properties of Cs-intercalated singlewalled carbon nanotubes (SWNTs). A detailed analysis of the 13 C and 133 Cs nuclear magnetic resonance (NMR) spectra reveals an increased metallization of the pristine SWNTs under Cs intercalation. The ‘metallization’ of Cs x C materials where x =0–0.144 is evidenced from the increased local electronic density of states (DOS) n ( E F)at the Fermi level of the SWNTs as determined from spin–lattice relaxation measurements. In particular, there are two distinct electronic phases called α and β and the transition between these occurs around x = 0.05. The electronic DOS at the Fermi level increases monotonically at low intercalation levels x <0.05 (α-phase), whereas it reaches a plateau in the range 0.05 < x < 0.143 at high intercalation levels (β-phase). The new β-phase is accompanied by a hybridization of Cs(6s) orbitals with C(sp2)orbitals of the SWNTs. In both phases, two types of metallic nanotubes are found with a low and a high local n ( E F), corresponding to different local electronic band structures of the SWNTs.