14 Photoenergy Conversion (Dye-Sensitized Solar Cells)
521
as anchoring groups on the electron-donating moiety (diphenylamine) connecting to
an electron-accepting moiety (dicyanovinylene for DYE30, DYE31, and DYE 34 or
1,3-diethyl-2-thioxodihydropyrimideine-4,6-dione for DYE32 and DYE 35) through
different π-linkers, and their related derivatives (DYE33 and O7) were designed and
developed (Fig. 14.41) (Yen et al. 2011; Ji et al. 2011). The NiO DSSCs using the
dyes with two carboxyl groups showed higher V oc , J sc , and η values than those of
the dyes with one carboxyl group. The relatively high V oc values of the dyes with
two carboxyl groups are attributed to efficient suppression of charge recombination
(dark current) between the holes in the NiO VB and the I
− ions in the electrolyte.
The NiO DSSCs using O7 with two carboxyl groups on diphenylamine connecting
to a dicyanovinyl group through an EDOT linker showed an η value of 0.060% with
a J sc value of 1.74 mA cm
−2 , a V oc value of 90 mV, and a ff value of 0.38, and a
maximum IPCE value of 18% (Ji et al. 2011).
Fig. 14.41 Chemical structures of An–D–π–A fluorene dye sensitizers DYE30–32, DYE34, and
DYE35 and their related derivatives DYE33 and O7 for NiO DSSCs
521
as anchoring groups on the electron-donating moiety (diphenylamine) connecting to
an electron-accepting moiety (dicyanovinylene for DYE30, DYE31, and DYE 34 or
1,3-diethyl-2-thioxodihydropyrimideine-4,6-dione for DYE32 and DYE 35) through
different π-linkers, and their related derivatives (DYE33 and O7) were designed and
developed (Fig. 14.41) (Yen et al. 2011; Ji et al. 2011). The NiO DSSCs using the
dyes with two carboxyl groups showed higher V oc , J sc , and η values than those of
the dyes with one carboxyl group. The relatively high V oc values of the dyes with
two carboxyl groups are attributed to efficient suppression of charge recombination
(dark current) between the holes in the NiO VB and the I
− ions in the electrolyte.
The NiO DSSCs using O7 with two carboxyl groups on diphenylamine connecting
to a dicyanovinyl group through an EDOT linker showed an η value of 0.060% with
a J sc value of 1.74 mA cm
−2 , a V oc value of 90 mV, and a ff value of 0.38, and a
maximum IPCE value of 18% (Ji et al. 2011).
Fig. 14.41 Chemical structures of An–D–π–A fluorene dye sensitizers DYE30–32, DYE34, and
DYE35 and their related derivatives DYE33 and O7 for NiO DSSCs