separator as a multifunctional polysulfide barrier for high- · 2018-06-19 · 1 supplementary...
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Supplementary Information
Vertical Co9S8 hollow nanowall arrays grown on Celgard
separator as a multifunctional polysulfide barrier for high-
performance Li-S batteries
Jiarui He,a,b Yuanfu Chen,b,* and Arumugam Manthirama,*
a Materials Science and Engineering Program & Texas Materials Institute, The University of Texas at Austin, Austin, TX 78712, USAE-mail: [email protected]
b State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, PR China
E-mail: [email protected]
Fig. S1 Photographs of as-prepared MOF-Celgard separator: (a) Front side, (b) back side, and (c) folded; (d) scalable production of MOF-Celgard separator.
Electronic Supplementary Material (ESI) for Energy & Environmental Science.This journal is © The Royal Society of Chemistry 2018
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Fig. S2 Photographs of Co9S8-Celgard separator.
Fig. S3 (a) XRD patterns of MOF, Celgard, and MOF-Celgard separators. (b, c and d) Top-surface morphology of MOF-Celgard at various magnifications. The inset shows a digital photo. (e, f and g) Cross-sectional morphologies of MOF-Celgard, and the corresponding elemental mapping images of (h) cobalt and (i) carbon.
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Fig. S4 SEM images of Celgard separator.
Fig. S5 (a) SEM image of Co9S8-Celgard separator from top surface and the corresponding elemental mapping images of (b) sulfur, (c) cobalt, and (d) carbon. (e) EDX spectrum of Co9S8-Celgard separator from top surface.
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0.0 0.2 0.4 0.6 0.8 1.0
0
50
100
150
Volu
me
Abso
rbed
(cm
3 g-1)
P/P0
MOF Co9S8 arrays
10 1000.000
0.001
0.002 MOF Co9S8 arrays
dV/d
D (c
m3 g
-1 n
m-1)
Pore Size (nm)
a b
Fig. S6 (a) The specific surface area and (b) pore size distribution of MOF and Co9S8.
Fig. S7 Photographs of (a) Co9S8-Celgard and (b) MOF-Celgard separator with repeatedly bending 50 times.
Fig. S8 SEM images of the sulfur cathode.
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1.8 2.1 2.4 2.7 3.0-2
-1
0
1
2
3
Curr
ent (
mA
cm-2)
Potential (V)
1st 2nd 3rd
Fig. S9 CV curves of the Li-S batteries with Co9S8-Celgard separator at 0.1 mV s-1 at 1.8 - 2.8 V.
0 20 40 601.8
2.1
2.4
2.7
Pote
ntia
l (V)
1st 10th 20th 30th
Specific Capacity (mA h g-1)
Fig. S10 Charge/discharge curve of Co9S8 at 0.1 C rate, the specific capacity is calculated by the weight of Co9S8.
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10μm
a
10μm
b
c d
10μm 10μm
Fig. S11 SEM images of (a) fresh Li foil, (b) cycled Li foil in the cell with the Co9S8-Celgard separator, (c) cycled Li foil in the cell with the MOF-Celgard separator, and (d) cycled Li foil in the control cell with bare Celgard separator after 200 cycles.
20μm
d e
a b
FS
c
f
O
Co5μm
g
Fig. S12 (a, b) SEM images of Co9S8-Celgard separator from top surface after 200 cycles and the corresponding elemental mapping of (c) cobalt, (d) sulfur, (e) fluorine, and (f) oxygen. (g) EDX spectrum of Co9S8-Celgard separator top surface after 200 cycles.
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Fig. S13 SEM images of Co9S8-Celgard separator from top surface at (a) discharge and (b) charge states.
Fig. S14 SEM images of the MOF-Celgard separator from the top surface after 200 cycles.
0 50 100 150 2000
400
800
1200
1600
Spec
ific
Capa
city
(mAh
g-1)
Cycle Number
2 mg cm-2
3.5 mg cm-2
5.6 mg cm-2
Fig. S15 Cycling performances of Li-S cells with high sulfur loading cathodes with Co9S8-Celgard separators.
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0 30 60 90 1200
20
40
60 Celgard MOF-Celgard Co9S8-Celgard
-Z'' (
ohm
)
Z' (ohm)Fig. S16 EIS plots of the fresh cells with Celgard, MOF-Celgard, and Co9S8-Celgard separators.
2000 1800 1600 1400 1200 1000 800 600
Tran
sim
itanc
e (a
.u.)
Wavenumber (cm-1)
Celgard MOF-Celgard MOF-Celgard cycled
Co=S
Fig. S17 IR spectra of the MOF-Celgard separators before and after the electrochemical process.