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collect Raman spectra on samples deposited on glass substrates
with an Invia Renishaw microspectrometer. For TEM imaging, a con-
centrated dispersion of the sample was drop-cast on a copper grid
(3.00 mm, 200 mesh, coated with carbon film), after evaporation of
the solvent under vacuum, the samples were analysed with a Phi-
lips EM 208 microscope operating at 100 kV. MALDI-TOF mass
spectra were recorded with a MALDI-TOF Bruker, autoflex II TOF/
TOF. The analyses were conducted in positive detection mode and
dithranol was added as matrix. The NMR experiments for DI-3thp
were carried out with a Bruker Advance III operating at 600 MHz
Transmission electron microscopy
The different derivatives were investigated by TEM. Typical
images are shown in Figure 9 for CNHs-TRI-3tph, indicating
that the unique structure of CNHs as well as their spherical ag-
gregates are preserved after the functionalisation. The preser-
vation of the graphitic structure likely implies the preservation
of the electronic properties, in agreement with our initial
thoughts and with other reports.[36]
1
for H NMR and at 150 MHz for 13C NMR experiments. For the anal-
ysis of TETRA-3tph, a 500 MHz (Varian, Inova) for 1H NMR and at
100 MHz for 13C NMR was used. A 400 MHz (Varian, VNMRS) was
used for the study of TRI-1tph and TRI-2tph. A 600 MHz spectrom-
eter was equipped with a cryogenic probe, which can significantly
increase the S/N ratio of NMR spectroscopy,[37] and makes it possi-
ble to study samples that aggregate at elevated concentration. All
1D and 2D NMR experiments (gCOSY, gTOCSY, gHSQC, gHMBC)
were performed at 298 K by using standard pulse sequences from
Agilent and Bruker libraries. CD3OD was used as solvent for DI-
3tph and TETRA-3tph, whereas CDCl3 was used for TRI-1tph and
TRI-2tph. MestreNova (v. 10.0) was used for data processing.
Figure 9. TEM images of p-CNHs (left) and CNHs-TRI-3tph (centre, right).
Scale bar 100 nm.
General procedure for the synthesis of oligothiophenephenylvi-
nylene (TRI-1tph, TRI-2tph, TRI-3tph, DI-3tph and TETRA-3tph):
Under a dry, inert atmosphere, tBuOK (9 equiv.) was added to a so-
lution of the corresponding aldehyde 4, 5 or 6 (1.1 equiv.) and (di-
ethoxyphosphorylmethyl)benzene 1, 2 or 3 (1 equiv.) in anhydrous
THF (20 mL) at À708C. The reaction mixture was stirred for 12 h at
À708C, then the crude material was warmed to RT and the solvent
was removed under reduced pressure. The crude material was dis-
persed in brine (50 mL) and the resulting dispersion was filtered
and washed with brine (200 mL) and distilled H2O (500 mL). The
final product was dried under high vacuum.
Conclusion
Three interesting new systems made of CNHs and OTP deriva-
tives with linear, star and cruciform shape have been designed
and fully characterised. A special emphasis has been devoted
to shedding light on the nature of the interaction between the
donor and acceptor systems. The effective interaction between
the organic molecule and the CNHs has been clearly ascer-
tained by using several techniques. The synthetic strategy
allows us to tune the platform with the corresponding mole-
cule for the desired application. The assembled systems have
been successfully applied for the design of dye-sensitised solar
cells. Currently, we are successfully applying the terthienyl dye
as an additive on CNHs in the design of dye-sensitised solar
cells. Preliminary results that compare solar cells with CNHs or
with an analogous TiO2 show an increase in the efficiency for
the former up to 6.24%. A complete study will be reported
somewhere else.
1
TRI-1tph: Yield: 97%; pale-yellow solid; H NMR (400 MHz, CDCl3):
d=7.46 (s, 3H; Ar-H), 7.32 (d, J=16.2 Hz, 3H; H-1 vipnyl), 7.23 (d,
J=5 Hz, 3H; H-3 tph), 7.11 (d, J=3.7 Hz, 3H; H-5 tph), 7.03 (dd, J=
5, 3.7 Hz, 3H; H-4 tph), 6.95 ppm (d, J=16.2 Hz, 3H; H-2 vinyl);
FTIR (KBr): n˜ =3095, 1623, 1584, 1041 957, 836, 806, 700, 542,
497 cmÀ1; MS (MALDI-TOF): m/z: calcd. for C24H18S3: 402.59; found:
401.90 [M]+.
TRI-2tph: Yield: 96%; yellow solid; 1H NMR (400 MHz,CDCl3): d=
7.44 (s, 3H; Ar-H), 7.26 (d, J=16 Hz, 3H; H-1 vinyl), 7.25 (d, J=
3.7 Hz, 3H; tph), 7.22 (d, J=3.7 Hz, 3H; tph), 7.11 (d, J=3.7 Hz, 3H;
tph), 7.04 (dd, J=3.5, 4 Hz, 3H; tph), 7.00 (d, J=3.5 Hz, 3H; tph),
6.90 ppm (d, J=16 Hz, 3H; H-2 vinyl); FTIR (KBr): n˜ =3066, 3019,
1617, 1584, 1044, 951, 841, 814, 793, 691, 554, 476 cmÀ1; MS
(MALDI-TOF): m/z: calcd. for C36H24S6: 648.97; found: 648.363 [M]+.
Raman spectra suggest promising results in SERS. A signifi-
cant enhancement of the Raman signal of the terthienyl deriv-
ative was observed during the synthesis of these new deriva-
tives. The application of these hybrid materials in this field will
be reported elsewhere. Therefore, this rational design ap-
proach makes it possible to combine an attractive platform
such as CNHs with a wide range of molecules, thereby extend-
ing their possible applications.
TRI-3tph: Yield: 88%; yellow solid; FTIR (KBr): n˜ =3063, 2923, 1585,
1423, 1064, 944, 833, 797, 688, 457 cmÀ1; MS (MALDI-TOF): m/z:
calcd. for C48H30S9: 893.98; found: 894.165 [M]+. This material was
insufficiently soluble to obtain useful NMR spectra.
1
DI-3tph: Yield: 94%; orange solid; H NMR (600 MHz, CD3OD): d=
7.72 (dd, J=5.7, 3.3 Hz, 2H; H-2 vinyl), 7.62 (m, 2H; H-1 vinyl), 7.45
(d, J=3.8 Hz, 2H; tph), 7.34 (dd, J=5.1, 1.1 Hz, 2H; tph), 7.25 (dd,
J=3.6, 1.1 Hz, 2H; tph), 7.19 (d, J=3.8 Hz, 2H; tph), 7.14 (m, 4H;
tph), 7.05 ppm (dd, J=5.1, 1.1 Hz, 2H; tph); 13C NMR (600 MHz,
CD3OD): d=143.3 (C48), 141.2 (C48), 137.9 (C48), 132.1 (C-vinyl),
131.4 (tph), 129.6 (C-vinyl), 128.7 (tph), 125.6 (tph), 125.2 (tph),
124.7 (tph), 124.4 ppm (tph); FTIR (KBr): n˜ =3065, 3018, 1497, 1426,
1064, 956, 833, 797, 689, 528, 465 cmÀ1; MS (MALDI-TOF): m/z:
calcd. for C48H30S9: 622.91; found: 622.146 [M]+.
Experimental Section
UV/Vis spectra were recorded with a Varian Cary 5000 spectropho-
tometer using 1 cm path-length quartz cuvettes. Fluorescence
measurements were carried out with a Cary Eclipse Fluorescence
spectrophotometer using 1 cm quartz path-length cuvettes. Ther-
mograms were recorded with a thermogravimetric analyzer Q50
(TA Instruments). The analyses were performed under N2 from 100
to 9008C by using a 108CminÀ1 ramp. A 633 nm laser was used to
Chem. Eur. J. 2016, 22, 11643 – 11651
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