dc.description.abstract | We successfully synthesize a series of bis-thiol-substituted
calix{[}4]arene derivatives bearing diverse groups on the
upper-rim/lower-rim (C@SH-1, C@SH-2, C@SH-3, C@SH-4, C@SH-5). For the
first time, we apply these derivatives as interface modifiers for
improving the photovoltaic response of a Ru-bipy dye (N-719)-sensitized
TiO2 photoanode in dye-sensitized solar cells (DSSCs). We use FT-IR, H-
and C-NMR, UV-vis spectrophotometry, and elemental analysis techniques
to characterize the structures of the calix {[}4]arene derivatives. We
achieve an overall photon-to-electron conversion efficiency (PCE) of
12.97\% with the DSSCs based on
25,27-bis(5-thiol-1-oxypentane)-26,28-dihydroxycalix{[}4]arene
(C@SH-3)-modified TiO2 photoanode (J(sc) = 9.49 mA cm(-2), V-oc = 672
mV, FF = 61.1\%) compared with a system of bare TiO2 (PCE: 6.82\%) under
AM 1.5G illumination of 300 W/m(2). In addition, we also study the
influence of the chain length (C@SH-2, with 3 carbons and C@SH-3, with 5
carbons) and subsidiary ligand groups such as alkyl (C@SH-1), nitro
(C@SH-4), and amine (C@SH-5) on the surface morphology, spectral
response, and photovoltaic performance. Our results reveal that the
C@SH-3 calixarene is the best derivative for modifiying the TiO2
photoanode. Thiol-functionalized Calix{[}4]arene molecules play a role
in assisting charge separation and preventing back recombination, which
accounts for the observed enhancement in photovoltaic performance. (C)
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