|
Abstract
|
Butterfly nanostructures were designed using multi-walled carbon nanotubes (CNTs) grafted with regioregular
poly(3-hexylthiophene) (RR-P3HT) chains (CNT-graft-P3HT). The secondary crystallization of RR-P3HT free chains onto
CNT-graft-P3HT reflected the donor–acceptor supramolecules with a butterfly configuration, in which the CNT acted as
the body of the butterfly and seeded crystallization of P3HT free chains resulted in the wings having a width of 37–38 nm. Butterfly supramolecules demonstrated high melting point (241.2 ∘C), fusion enthalpy (31.5 J g−1) and crystallinity (85.13%). High
photoluminescence quenching and thus donating–accepting property were also detected for the butterfly nanohybrids with a
bandgap energy of 1.94 eV. Incorporation of butterfly nanostructures in the active layer of photovoltaic devices (P3HT:butterfly)
conspicuously affected the system characteristics including short circuit current density (Jsc; 10.84 mA cm−2), fill factor (FF; 56%)
and power conversion efficiency (PCE; 3.94%). The inclusion of phenyl-C71-butyric acid methyl ester molecules as second
acceptor in thin-film active layers further increased the efficacy of systems, i.e. Jsc of 12.23 mA cm−2, FF of 63%, open circuit
voltage of 0.66 V and PCE of 5.08%, without considering external treatments and additives.
|