Kinetic study of photopolymerization and depolymerization in C60 films using in situ Fourier-transform infrared spectroscopy for development of C60-based thermoelectric materials

Kinetics of photopolymerization and thermal-induced depolymerization in C60filmsfound that the proportion of the monomer, dimer, and oligomers was saturated to be 4, 72, and 24%, respectively,after40 h irradiation of ultraviolet light. Depolymerization kinetics of the photopolymerized C60film obtainedthe activation energy (Ea) of depolymerization for (C60)2dimerto be 1.26 eV, whereasEafor (C60)noligomers to be 1.78 eV. The difference inEabetween them can be utilized to change their proportion distributions by iterations of photoirradiation/thermal-depolymerization cycle to control the physicochemical properties (such as the electronic and thermal conductivities) of photopolymerized C60film.