Fullerene proton conductors

AC impedance of electronically insulative polyhydroxyfullerene C60(OH)12 showed conductivity of 7×10−6 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.