Article
BULLETIN OF THE
ISSN (Print) 0253-2964 | (Online) 1229-5949
KOREAN CHEMICAL SOCIETY
Logic Science Instruments model VSP potentiostat using a
three-electrode cell system composed of an Ag/AgCl refer-
ence electrode, platinum wire counter electrode, and copper
working electrode, wherein the potential window was
between +2 and −2 V. We prepared a working electrode
system by dipping a copper electrode in a hexane solution
of the synthesized silole derivatives and then evaporating
the solvent in a dry oven. The morphologies and surface
analysis of the battery cell anodes were examined by field
emission scanning electron microscopy with SEM Hitachi
S-4800 (Ibaraki, Japan). The cell properties of the charge/
discharge experiments were performed using a multi-
channel potentiostat/galvanostat of WonATech WMPG-
2,5-Dibromo-1,1,3,4-tetraphenyl-silole (3b) was pre-
pared by the intramolecular reductive cyclization of com-
pound 2b and subsequent bromination following previous
11,17,20
literature.
A white powder of the product 3b (4.18 g,
1
5
9.13%) was obtained. H NMR (500 MHz, CDCl ): δ
3
13
7
.02(m, 4H), 7.18(m, 6H), 7.53(m, 6H), 7.86(m, 4H),
C
NMR (125 MHz, CDCl ): δ 120.041, 127.595, 127.624,
3
1
1
27.969, 128.507, 129.025, 131.194, 135.782, 136.896,
29
58.215. Si NMR (99 MHz, CDCl ): δ −16.49. IR (neat)
3
νmax: 3051(varC H), 1487, 1472, 1426(varC C), 1076, 1057,
−1
1
024(vC-Br), 769, 737, 717, 695(v
) cm . UV–Vis
Si C
−1
−1
3
(
THF) λmax, nm (ε, cm M ): 333 (2.18 × 10 ).
,1-Diisopropyl-2,5-bis(trimethylsilyl)-3,4-diphenyl-
silole (4a) was synthesized by the intramolecular reductive
cyclization of compound 3a and subsequent
trimethylsilation according to previous reports.
1
1000. Electrochemical impedance spectroscopy was
11,17,20
performed using a VersaSTAT 3 Model 500 Potentiostat
Galvanostat of AMETEK Scientific Instrument (Kingston,
UK) with VersaStudio 2.60.0 Software of Princeton
Applied Research (New Jersey, USA).
A
white powder of the product 4a (3.57 g, 48.8%) was
1
obtained. H NMR (500 MHz, CDCl ): δ −0.17(s, 18H),
3
1.15(d, 12H, J = 7.4 Hz), 1.44(m, 2H), 6.79(m, 4H), 7.01
13
Diisopropyldi(phenylethynyl)silane (2a) was prepared
by the reaction of dichlorodiisopropylsilane (1a) with
phenylacetylene that was treated with n-butyllithium fol-
(m, 6H). C NMR (125 MHz, CDCl ): δ 1.181, 11.884,
3
18.421, 125.897, 126.934, 129.190, 140.842, 143.453,
2
9
171.933. Si NMR (99 MHz, CDCl ): δ −9.92, 35.60. IR
3
1
1,17,20
lowing the procedure reported in the literature.
A
(neat) νmax: 3059(varC H), 2947, 2863(valC H), 1458
(varC C), 831, 776, 758, 698(v
λmax, nm (ε, cm M ): 303 (1.85 × 10 ).
1,1,3,4-tetraphenyl-2,5-bis(trimethylsilyl)-silole
−
1
yellowish viscous liquid of the product 2a (33.6 g, 99.0%)
) cm . UV–Vis (THF)
Si C
1
−1
−1
3
was obtained. H NMR (500 MHz, CDCl ): δ 1.24 (m,
3
1
3
2
CH(CH ) , 14H), 7.35 (m, 6H), 7.56 (m, 4H). C NMR
(4b)
3
2
(
1
−
(
(
125 MHz, CDCl ): δ 12.478, 17.718, 87.559, 107.073,
was synthesized by the intramolecular reductive cyclization
3
2
9
22.834, 128.727, 132.192. Si NMR (99 MHz, CDCl ): δ
of compound 3b, followed by trimethylsilation according
3
1
1,17,20
23.139. IR (neat) νmax: 3057 (varC-H), 2954, 2865
to previous literature.
A pale yellowish powder of
1
valC H), 2157 (vC C), 1595, 1573, 1487, 1460, 1442
the product 4b (3.51 g, 41.9%) was obtained. H NMR
−1
varC C), 831, 754, 725, 686 (vSi C) cm .
(500 MHz, CDCl ): δ 0.00(s, 18H), 7.34(m, 4H), 7.47(m,
3
13
Diphenyldi(phenylethynyl)silane (2b) was prepared by
6H), 7.86(m, 6H), 8.23(m, 4H). C NMR (125 MHz,
the reaction of dichlorodiphenylsilane (1b) with
phenylacetylene that was treated with n-butyllithium by
CDCl ): δ 0.700, 126.184, 126.990, 127.931, 128.756,
3
129.726, 132.634, 135.667, 142.607, 143.663, 171.662.
1
1,17,20
29
means of the literature.
the product 2b (29.3 g, 97.0%) was obtained. H NMR
A yellowish viscous liquid of
Si NMR (99 MHz, CDCl ): δ −8.86, 8.41. IR (neat))
3
1
νmax: 3066(varC H), 2964, 2892(valC H), 1470, 1428
(v
cm . UV–Vis (THF) λmax
311 (2.12 × 10 ).
(
500 MHz, CDCl ): δ 7.38 (m, 6H), 7.48 (m, 6H), 7.63 (m,
), 1242(vC C), 833, 778, 759, 737, 697 (v
)
3
arC C
−1
Si C
−1
1
3
−1
4
8
1
H), 7.92 (m, 4H). C NMR (125 MHz, CDCl ): δ
,
nm (ε, cm
M ):
3
3
7.733, 108.917, 122.519, 128.249, 128.403, 129.372,
2
9
30.418, 132.492, 133.125, 135.064. Si NMR (99 MHz,
Fabrication of the anode materials for lithium-ion batte-
ries. The active materials 3a, 4a, or 4b were mixed with
Super P and polyvinylidenefluoride (PVDF) in a ratio of
30:60:10 (wt %). Following this, the mixtures were stirred
using zirconia ball-milling with N-methylpyrrolidone
(NMP) as the solvent for 24 h. The well-mixed electrode
material solution was coated onto a Cu foil current collec-
tor, using a doctor blade. The coated active material was
CDCl ): δ −48.02. IR (neat) νmax: 3068, 3019(varC H),
3
2
6
157(vC C), 1487, 1441, 1429(varC C), 881, 834, 752, 741,
−1
88(vSi C) cm .
,5-Dibromo-1,1-diisopropyl-3,4-diphenyl-silole (3a)
2
was prepared by the intramolecular reductive cyclization of
compound 2a, followed by bromination as per previous lit-
1
1,17,20
erature.
5
A white powder of the product 3a (4.38 g,
1
ꢀ
8.23%) was obtained. H NMR (500 MHz, CDCl ): δ
then vacuum-dried at 50 C and the temperature was gradu-
3
ꢀ
1
.26(d, 12H, J = 7.4 Hz), 1.52(m, 2H), 6.94(m, 4H), 7.15
ally increased to 110 C for 12 h to remove the NMP sol-
13
(m, 6H). C NMR (125 MHz, CDCl ): δ 9.800, 17.171,
vent. The cell assembly of the 2032 type coin cell for the
electrochemical properties experiment was carried out
inside a glove box filled with Ar gas. Batteries were fabri-
cated into half cells, and the prepared active materials were
used as working electrodes with a thickness of 10 μm. Lith-
ium metal was used as the counter electrode and polypro-
pylene (PP) was used as the separator. The electrolyte was
3
1
19.772, 127.345, 127.547, 128.958, 137.289, 157.869.
2
9
Si NMR (99 MHz, CDCl ): δ 7.463. IR (neat)) νmax:
3
3056, 3018(varC H), 2952, 2864(valC H), 1488, 1459, 1441
(
v
), 1075, 1022(vC-Br), 766, 694, 672, 642(v
)
arC C
−
Si C
−1
1
−1
cm . UV–Vis (THF) λmax
3
,
nm (ε, cm
M ):
3
25 (1.91 × 10 ).
Bull. Korean Chem. Soc. 2021, Vol. 42, 380–387
© 2020 Korean Chemical Society, Seoul & Wiley-VCH GmbH
www.bkcs.wiley-vch.de
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