Sample preparation

Sample preparation. The structure of CoPOM and ZnPOM have been previously reported. The complexes used in this work have been synthesized using the procedure described for the analogous MnII compound but using Co(SO4) and Zn(SO4) instead of Mn(SO4). HiPCo SWNTs were purchased from Carbon Inc. and purified by the gas phase method. All the solutions were prepared using Millipore water. Functionalisation of pNTs by MPOM (M = Co or Zn) was achieved as follows: 2 mg of pNTs were added to 7.5mL of a 5.10M solution of MPOM in a 10 M dichloroacetic acid buffer whose pH has been previously adjusted to 2 by adding dilute sodium hydroxide dropwise. The mixture was stirred in an ultrasonic bath for 20 hours while maintaining the temperature of the bath below 12 °C to prevent damaging of the pNTs. This led to a dark suspension that was subsequently centrifugated under 14 000 g for 20 minutes. The supernatant was isolated, filtered on a nanoporous membrane and washed with water, giving rise to a grey glassy mat of MPOM@NTs. The sediments could be redispersed in pure water and after centrifugation, the supernatant led to identical grey glassy mats. XPS, Raman and magnetization measurements samples were obtained by filtering the supernatant resulting of the centrifugation of the black aqueous MPOM-NTs suspensions on nanoporous membranes. For the electron microscopy experiments, the supernatant was first filtered on a nanoporous membrane, washed with water and redispersed in a minimum amount of water. Eventually, a few drops of this suspension were cast on carbon lacey grids.