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A new zinc phthalocyanine-zinc porphyrin dyad (ZnPc-ZnP) fused through a pyrazine ring has been synthesized as a receptor for imidazole-substituted C60 (C60Im) electron acceptor. Self-assembly via metal-ligand axial coordination and the pertinent association constants in solution were determined by 1H-NMR, UV-Vis and fluorescence titration experiments at room temperature. The designed host was able to bind up to two C60Im electron acceptor guest molecules to yield C60Im:ZnPc-ZnP:ImC60 donor-acceptor supramolecular complex. The spectral data showed that the two binding sites behave independently with binding constants similar in magnitude. Steady-state fluorescence studies were indicative of an efficient singlet-singlet energy transfer from zinc porphyrin to zinc phthalocyanine within the fused dyad. Accordingly, the transient absorption studies covering a wide timescale of femto-to-milli seconds revealed ultrafast energy transfer from 1ZnP* to ZnPc (kEnT ~ 1012 s-1) in the fused dyad. Further, a photo induced electron transfer was observed in the supramolecularly assembled C60Im:ZnPc-ZnP:ImC60 donor-acceptor complex leading to charge separated states, which persisted for about 200ns. Support from the Ministerio de Economia Industria y Competitividad of Spain (CTQ2014-55798-R and CTQ2017- 87102-R) The Special Research Account of the University of Crete, US-National Science Foundation (grant no. 1401188 to FD)

The superoxide anion radical, O2•−, induced C60 electropolymerization mechanism was refined by simultaneous cyclic voltammetric (CV) and vis-NIR spectroelectrochemical as well as mass spectrometric (MALDI-TOF) characterization of the one- and two-electron reduction products of C60 in the presence of O2 in a mixed organic solvent solution. The C60 polymer (C60-O) film was also investigated by Raman spectroscopy and imaged by atomic force microscopy (AFM) both at the early and advanced polymerization stage. While the spectroelectrochemical behavior of the C60/C60•− couple in the presence of O2 was similar to that in its absence, at more negative potentials corresponding to C602− and O2•− formation C602− participated in a chemical follow-up reaction resulting in a product lacking any diagnostic absorption band in the vis-NIR range. Although the main peak in the MS spectrum of the one-electron reduction product was that of C60 at m/z of 720, several additional peaks in the m/z range of 739−760 appeared, indic...

Thin-solid films of C76, C78 and C84 were prepared from chloroform solutions by drop coating on electrodes of quartz crystals and investigated by simultaneous cyclic voltammetry and piezoelectric microgravimetry with the use of an electrochemical quartz crystal microbalance. Stability of the films with respect to dissolution in acetonitrile solutions was dependent on the fullerene oxidation state as well as nature of both the fullerene and the counter cation, i.e., tetrabutylammonium (TBA+) or K+, of the supporting electrolyte. The TBA+ counter cation ingress to the films for compensation of a negative charge of the generated reduced fullerenes was accompanied by intake of the acetonitrile solvent. The number of acetonitrile molecules per one TBA+ cation entering the film was higher the higher the fullerene.