Fullerene proton conductors

AC impedance of electronically insulative polyhydroxyfullerene C-60(OH),I showed conductivity of 7 x 10(-6) S/cm at 295 K, which is attributable to proton conductivity. Activation energy of proton conduction in this material was 0.33 eV and it may correspond to the proton-hopping energy. Drift of the water molecules through the bulk was negligible because proton conductivity did not change for over 10 h, while a direct current of protons was flowing in dry hydrogen gas. (C) 2001 Elsevier Science B.V. All rights reserved.