Photophysical properties and potential application in photocurrent generation of porphyrin-[60]fullerene polymer linked by metal axial coordination

Porphyrin-[60]fullerene polymers linked by metal axial coordination of fullerenoacetic diacids e-isomer with dihydroxo Sn(IV) porphyrin have been prepared and characterized. The polymers display the regular one-dimensional linear arrays with lengths exceeded 200 nm and show good thermal stability. The efficient photoinduced electron transfer from singlet excited porphyrin to fullerene in the polymer has been achieved resulting in the formation of charge separation state with a lifetime as long as 140 μs in benzonitrile. The long-lived charge separated state is very useful for photoelectric conversion system. The photocurrent generation in organic photovoltaic device was described further, and a steady and rapid cathodic photocurrent response was produced at the irradiation of λ_ex = 429 nm light. The polymers are expected to provide novel photonic or electronic functions in organic solar cell.