Ionic Charge-Selective Electron Transfer at Fullerene-Multilayered Architecture on an Indium−Tin Oxide Surface

Abstract

We report the first observation of the ionic charge-selective electron transfer at the fullerene-multilayered indium−tin oxide (ITO) electrode. The surface of the ITO electrode was modified by three layers of self-assembled fullerene/1,12-diaminododecane. The fullerene concentration in each layer was quantitatively measured by Rutherford backscattering spectrometry and UV spectrometry. Electron transfer was not observed from the electrode to the negatively charged Fe(CN)63-, but smooth electron transfer was made to the positively charged Ru(NH3)63+ in an aqueous solution. At the extremely low concentration of Ru(NH3)63+, 2 × 10-6 M, the bare ITO could not detect the ruthenium complex, but the fullerene-multilayered electrode identified the presence of the cationic ruthenium complex, indicating the enrichment of the ruthenium cationic complex in the vicinity of the electrode.