Photoelectric response of a gold electrode modified with self-assembled monolayers of pyrrolidinofullerenes

Three new fullerene derivatives 1, 2 and 3 have been synthesized, which can form stable self-assembled monolayers (SAMs) on a gold surface. These SAMs were characterized by contact angle measurements and scanning tunneling microscopy. The photoelectric conversion properties of the SAMs have also been investigated. Photocurrent action spectra show that the excited fullerene derivatives 1, 2 and 3 act as photoactive species in the photoinduced electron transfer process. Factors such as intensity of irradiation and bias voltage have been studied. The quantum yields of the SAMs range from 2.9 to 14.9% under the most favorable conditions.