Temperature Dependence of C60 Solubility in Different Solvents

Temperature dependence of C 60 solubility in four organic solvents, i.e., hexane, toluene, xylene and cyclohexane, above room temperature is investigated. It is found that the solubilities decrease as temperature rising in hexane, toluene and xylene indicating an exothermic process, while the solubility in cyclohexane increases with the temperature increase denoting an endothermic dissolving process. Least square fit gives the heat of solution of C 60 in hexane, toluene, xylene and cyclohexane as −6.0, −9.8, −9.1 and 48.2 kJ/mol respectively. A brief discussion is presented.