Supporting Information
Jacket-like Structure of Donor-Acceptor Chromophores-Based
Conducting Polymers for Photovoltaic Cell Applications
Yi-Lung Yang,1 Yi-Huan Lee,1 Chun-Jie Chang,1 Ang-Jhih Lu,1 Wei-Chun Hsu,1
Leeyih Wang,1 Man-kit Leung,1 and Chi-An Dai 1,2,*
1
Institute of Polymer Science and Engineering, National Taiwan University, No.1, Sec.
4, Roosevelt Rd. Taipei 10617, Taiwan
2
Department of Chemical Engineering, National Taiwan University, No.1, Sec. 4,
Roosevelt Rd. Taipei 10617, Taiwan
*Correspondence
to: Chi-An Dai (E-mail: polymer@ntu.edu.tw)
1
EXPERIMENTAL SECTION
Materials
THF and DMF were dried over and distilled from Na and CaH2 under an atmosphere
of dry nitrogen. 4,4'-Dibromobenzil (9; 97%, ACROS), benzyltrimethylammonium
chloride (98%, ACROS), potassium carbonate (K2CO3; 99%, ACROS),
tetrahydrofuran (THF; 99%, Mallinckrodt), tetrakis(triphenylphosphine)palladium(0)
(Pd(PPh3)4; 99%, ACROS), diethyl ether (99.9%, Mallinckrodt), MgSO4 (97%,
anhydrous, SHOWA), dichloromethane (99.5%, Mallinckrodt), petroleum ether
(ACROS), AcOH (99.8%, ACROS), toluene (99.5%, Mallinckrodt), MeOH (99.8%,
Mallinckrodt), DMF (99.5%, ACROS), and bromobenzene (99%, ACROS) were used
without further purification. All procedures involving air-sensitive reagents were
carried out under an atmosphere of high purity argon. Column chromatography was
performed on silica gel (230-400 mesh ASTM, Merck silica gel). Conductive ITO
coated glass was purchased from Merck Inc. Tetrabutylammonium perchlorate (TBAP)
was obtained from TCI and recrystallized twice from ethyl acetate and then was dried
in vacuo prior to use. All other chemical reagents were used as received from
commercial sources.
1-(4-(9-Butyl-9H-carbazol-3-yl)phenyl)-2-(4-(9-butyl-9H-carbazol-6-yl)phenyl)etha
ne-1, 2-dione (10)
A mixture of compounds 8 (15.31 g, 57.30 mmol), 9 (8.80 g, 23.90 mmol),
benzyltrimethylammonium chloride (0.20 g), potassium carbonate (16.58 g, 120.00
mmol), THF/water (240 mL; 1:1 in volume), and Pd(PPh3)4 catalyst (2.20 g) was
carefully degassed and charged with nitrogen. The reaction mixture was heated to
reflux for 24 h. After cooled to room temperature, the mixture was extracted with 300
mL of diethyl ether three times. The combined organic phase was separated, washed
with brine, dried over anhydrous sodium sulfate, and evaporated to dryness. The
residue was purified by column chromatography using a mixture of
dichloromethane/petroleum ether (1:1) as the eluent, affording the product of 13.80 g
as a yellow solid.
Yield: 88%. 1H NMR (400 MHz, CDCl3, ppm): δ 0.96 (t, J = 12 Hz, 6 H), 1.43(m,
4 H), 1.89 (m, 4 H), 4.34 (t, J = 14 Hz, 4 H), 7.27 (t, J = 8 Hz, 2H ), 7.44-7.53 (m, 6
H), 7.77 (d, J = 8 Hz, 2 H), 7.88 (d, J = 10 Hz, 4 H), 8.13 (d, J = 10 Hz, 4 H), 8.16 (d,
J = 8 Hz, 2 H), 8.39 (s, 2 H). 13C NMR (100 MHz, CDCl3, ppm): δ 13.86, 20.54,
31.11, 42.97, 109.00, 109.19, 119.25, 119.28, 120.47, 122.78, 123.48, 125.10, 126.11,
127.43, 130.20, 130.61, 130.92, 140.66, 140.94, 148.56, 194.48.
2
3-(4-(5,8-Dibromo-2-(4-(9-butyl-9H-carbazol-3-yl)phenyl)quinoxalin-3-yl)phenyl)-9
-butyl-9H-carbazole (M2)
A suspension of compound 3 (53.59 mg, 0.20 mmol) and 10 (65.28 mg, 0.10 mmol)
in 7 mL acetic acid was heated to reflux for 6 h, during which time a yellow
precipitate formed. After filtration, the resulting solid was purified by recrystallization
using a mixture of toluene/MeOH. The residue was purified by column
chromatography using a mixture of dichloromethane/petroleum ether (1:1) as the
eluent. The product was obtained of 73.01 mg as a yellow solid.
Yield: 83 %. 1H NMR (400 MHz, CDCl3, ppm): δ 0.94 (t, J = 15 Hz, 6 H), 1.43 (m,
4 H), 1.88 (m, 4 H), 4.32 (t, J = 14 Hz, 4 H), 7.22 (t, J = 8 Hz, 2 H), 7.40-7.49 (m, 6
H), 7.74-7.77 (m, 6 H), 7.86-7.89 (m, 6 H), 8.13 (d, J = 8 Hz, 2 H), 8.37 (s, 2 H). 13C
NMR (100 MHz, CDCl3, ppm): δ 13.91 20.59, 31.16, 42.98, 108.89, 109.03, 118.92,
119.02, 120.48, 122.94, 123.42, 123.68, 125.02, 125.88, 127.10, 130.79, 131.12,
132.87, 135.99, 139.30, 140.24, 140.92, 143.32, 153.91; IR (cm-1, KBr): 1626 (C=N
stretching), 1061 (C-N stretching). EI-MS calcd exact mass: m/z 882.2. Found: m/z
882.2.
PCPQT (P2)
A
mixture
of
3-(4-(5,8-dibromo-2-(4-(9-butyl-9H-carbazol-3-yl)phenyl)
quinoxalin-3-yl)phenyl)-9-butyl-9H-carbazole (M2) (0.60 g, 0.68 mmol) and
2,5-bis(trimethylstannyl)thiophene (11) (0.45 g, 0.68 mmol) in 13 mL DMF was
added Pd(PPh3)4 (0.04 g) in a flask under nitrogen atmosphere at room temperature.
The reaction mixture was stirred at 85-90 °C for 72 h. After the reaction is completed,
bromobenzene was added and the reaction is under reflux for 3hr to complete the
capping reaction. The polymer was purified by precipitation in methanol/water (10:1),
filtered through filter, and washed on a Soxhlet apparatus with methanol and
subsequently with acetone. The polymer was recovered with THF as a green dark
powder.
Yield: 95 %. 1H NMR (400 MHz, CDCl3, ppm): δ 6.74-8.43 (m, 26n H), 3.84-4.35
(m, 4n H), 0.58-1.91 (m, 14n H); IR (cm-1, KBr): 1626 (C=N stretching), 1061 (C-N
stretching), 768 (C-S-C stretching). Mw=11,000 (g/mol), Mn=5,700 (g/mol),
PDI=1.96.
PCPQT-purified (P2-P)
A preparative gel permeation chromatography technique with THF as the eluent was
used to remove monomers and oligomers of the as-synthesized PCPQT (P2) after the
polymerization. High molecular weight PCPQT (Mw=18,000 (g/mol)) with relatively
narrow polydispersity (PDI~1.48) was thus obtained and designated as P2-P. P2-P
3
was further purified by a TAAcOH (SiliaBond R69030B) surface modified silica gel
to remove any residual organometallic compounds. The preparative GPC technique
was conducted by using a Waters 2695 Alliance HPLC with a preparative column
(Polymer Laboratories Ltd, PLgel, 10 μm, 103 Å, Serial No.10M-3-69A-7) using
THF as the eluent with a flow rate of 4.8 mL/min at 25 °C.
Yield: 35 %. 1H NMR (400 MHz, CDCl3, ppm): δ 6.74-8.43 (m, 26n H), 3.84-4.35
(m, 4n H), 0.58-1.91 (m, 14n H); IR (cm-1, KBr): 1626 (C=N stretching), 1061 (C-N
stretching), 768 (C-S-C stretching). Mw=18,000 (g/mol), Mn=12,000 (g/mol),
PDI=1.48.
4
FIGURE S1 1H NMR spectra of compounds 10 (a) and M2 (c) in CDCl3; 13C NMR spectra of compounds 10 (b) and M2 (d) in CDCl3.
5
(a) 100
o
Td=426 C
90
o
Td=351 C
70
(b)
60
50
40
△H
Weight ratio (%)
80
o
Td=430 C
o
Tg=108 C
30
20
0
10
50
100
150
Temperature (oC)
200
0
100
200
300
400
500
600
700
o
Temperature ( C)
FIGURE S2 (a) TGA curves for Comparison of UV-vis absorption spectra of M2 (□), P1 (○), and P2 (△); (b) DSC trace of P2 (△).
6
1.0
Normailized Intensity
P1-film
0.8
P2-film
0.6
0.4
0.2
0.0
300
400
500
600
700
Wavelength (nm)
800
FIGURE S3 Comparison of UV-vis absorption spectra of P1 (○) and P2 (▲) in the film state.
7
900
N
N
N
N
Br
Br
M2
8
2
9
*
3
10
M1
11
6
12
7
13
*
8
14
11
15
P2
16
P2-P
17