ESR STUDY OF INTERACTION BETWEEN C-60 MOLECULES AND ZEOLITES HY OR NAY

An ESR investigation is performed to characterize the interaction betw een C60 molecules and the Y zeolite after impregnation from solutions. No ESR signal is observed after the adsorption of C60 on NaY zeolite (the non-acidic form), but an intensive signal is registered for C60 a dsorbed on HY zeolite (the acidic form), the parameters of the ESR spe ctra being dependent on the type of solvent used (DELTAH = 3.5 G upon C60 sorption from CCl4 or DELTAH = 9 G upon sorption from toluene). Th e adsorption of C60 molecules on HY is assumed to be followed by forma tion of C60+. cation-radicals on the electron-acceptor centers located at the entrances to the supercages. The ESR signal is registered afte r heating HY with C60 which is sorbed at 90-degrees-C in air. However, after evaporation of the solvent, the ESR signal disappears, and retu rns upon addition of the solvent.