om400796p_si_001.pdf (3.95 MB)
Divergent Synthesis and Tuning of the Electronic Structures of Cobalt–Dithiolene–Fullerene Complexes for Organic Solar Cells
journal contribution
posted on 2014-02-10, 00:00 authored by Yutaka Matsuo, Keisuke Ogumi, Masashi Maruyama, Takafumi NakagawaA pentakis(aryl)[60]fullerene
cobalt trisulfide complex (1a) was obtained from the
reaction of a pentakis(aryl)[60]fullerene
cobalt dicarbonyl complex (2a) with triphenylmethanethiol.
This reaction proceeded smoothly even at ambient temperature to produce 1a in moderate to high yield. The series of pentakis(aryl)[60]fullerene
cobalt dithiolene complexes 3–9 were
also synthesized by the reaction of 1a with a variety
of readily available disulfide compounds. The HOMO and LUMO levels
of the complexes could be tuned by making changes to the substituents
on the dithiolene ligands, with changes to the electronic structure
of the compounds influencing their photovoltaic performance, especially
in terms of their open-circuit voltage. Small-molecule organic solar
cells constructed from the naphthalene dithiolene complex 9 and tetrabenzoporphyrin showed a power conversion efficiency of
0.59%.