Electroabsorption spectra of a complex formed between tetraphenyl-porphyrin and fullerene in a polymer film

Electroabsorption spectra of a mixture of tetraphenylporphyrin (TPP) and fullerene (C60) doped in a polymer film have been measured for both free-base porphyrin and its zinc analog with different concentrations of C60. The absorption band whose peak is located in a wavelength region longer than the peak of the Soret band of TPP appears, as the concentration of C60 increases. This band is attributed to the absorption of a complex composed of TPP and C60. Electroabsorption spectra show that a charge separation occurs upon photoexcitation to the absorption band of the complex located near the Soret band of TPP.