Involved researchers : L. Alvarez, J.L. Bantignies, J.L.Sauvajol, R. Leparc, A. Zahab, R. Aznar
Collaborations : A. San Miguel, D. Machon (LPMCN, Lyon), M. Chorro, O. Mathon (BM 29, ESRF, Grenoble), P. Lagarde, J.P. Itié, A.M. Flank (SLS, Villigen, Switzerland), P. Launois, J. Cambedouzou, (LPS, Orsay)
Insertion of SWNT with halogens (iodine) improves the SWNT conductivity by charge transfer. Our works by X-ray absorption spectroscopy (EXAFS) in collaboration with the beamline BM29 at the ESRF synchrotron investigated the poly-iodides structure inside the nanotube (figure 1) and evidenced the presence of mainly disordered I5- chains. More recent investigations carried out by Raman and X-ray absorption spectroscopy at SLS suggest a strong modification of the charge transfer on the poly iodides chains under high pressure ( 8 GPa). Raman results could even be interpreted by considering a transformation of I5- chains into I3- chains under pressure.
Michel et al, EXAFS investigations of iodine-doped carbon nanotubes : PHYS.REV.B , 73, 195419, (2006)