SUPPORTING INFORMATION High-Voltage and Noncorrosive Ionic ...
SUPPORTING INFORMATION High-Voltage and Noncorrosive Ionic Liquid Electrolyte Used in Rechargeable Aluminum Battery Huali Wang, † Sichen Gu, † Ying Bai, †, ** Shi Chen, † Feng Wu, †, ‡ and Chuan Wu †, ‡, ** †
Beijing Key Laboratory of Environmental Science and Engineering, School of Materials
Science & Engineering, Beijing Institute of Technology, Beijing 100081, China ‡Collaborative Innovation Center of Electric Vehicles in Beijing, Beijing 100081, China
** Corresponding Authors: (Ying Bai) E-mail: [email protected] (Chuan Wu) E-mail: [email protected]
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Experiment Details: The reagents were obtained from commercial sources and used without further purification. [BMIM]OTF (99%) was bought from Shanghai Jie Cheng Chemical Co., Ltd. The Al(OTF)3 was bought from Alfa Aesar. The preparation of Al(OTF)3/[BMIM]OTF ionic liquid was performed in a glove box filled with inert gas Ar. Al(OTF)3 was added to the [BMIM]OTF ionic liquid under stirring at a series molar concentration (0, 0.05, 0.1, 0.5, 1mol/L). Infrared spectra of ionic liquids were obtained with a Nicolet iS10 Fourier Transform Infrared Spectroscopy (FTIR) spectrometer at 4 cm-1 resolution. Cyclic Voltammetry (CV) and ionic conductivity were both measured on CHI604D electrochemical workstation. In CV measurement, the glassy carbon (GC) disk electrode (diameter 2mm) was used as working electrode, Al metal was used as the counter electrode and reference electrode, and the scan rate is 10mV/s. In ionic conductivity test, a DJS-1 type conductivity electrode was used. V2O5 nanowire was synthesized similar to the method used previously. 0.364 g V2O5 and 5 mL 30wt% H2O2 were added to 30 mL water and magnetically stirred for 0.5h. Then, the prepared solution was transferred to a polytetrafluoroethene-lined stainless steel reactor and heated for four days at 205 ºC. Finally, the prepared product was taken out and washing with deionized water for several times. After 60 ºC vacuum drying for 24h, it is calcinated at 500 ºC for 4 hours in air to get the final product. Rechargeable aluminum battery (2025 coin-type cells) using Al(OTF)3/ [BMIM]OTF ionic liquid as electrolyte was assembled in an argon-filled glove box. The cathode was made with V2O5 nanowire: Super P: PTFE binder=8:1:1 (mass ratio) coated on Al foam. Whatman glass
S-2
fiber (GF/C) was selected as the separator, and Al metal foil (99.9999% Al purity) was used as the anode. Al anode is treated by immersing in AlCl3/[BMIM]Cl=1.1:1 ionic liquids for 24 hours, then it was taken out, washed with ethanol and dry. All Al treatment procedures are performed in glove box. AlCl3/[BMIM]Cl=1.1:1 ionic liquid was prepared by mixing AlCl3 with [BMIM]Cl according to molar ratio, then stirred overnight until homogeneous and clear liquid obtained. Galvanostatic charge–discharge test was performed on a LAND CT2001A battery tester in a potential range of 3–0.02 V, at the current density of 10 mA/g.
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Table S1. Frequencies and assignments of vibrations in Figure 1 [BMIM]OTF
0.05 mol/L
0.1 mol/L
0.5 mol/L
1 mol/L
(cm-1)
(cm-1)
(cm-1)
(cm-1)
(cm-1)
C4,5-H stretching
3154
3154
3154
3155
3156
C2-H stretching
3115
3115
3115
3116
3118
CH3 asymmetric stretching
2966
2966
2966
2967
2968
CH2 asymmetric stretching
2939
2939
2939
2940
2941
CH3 symmetric stretching
2878
2878
2878
2879
2880
C=N stretching
1575
1575
1575
1575
1575
CH3 asymmetric bending
1468
1468
1468
1467
1467
CH2 in-plane bending
1432
1432
1432
1431
1431
CH3 symmetric bending
1386
1386
1386
1386
1386
SO3 asymmetric stretching
1262
1262
1261
1261
1289
SO3 symmetric stretching
1225
1225
1225
1226
1227
CF3 asymmetric stretching
1162
1162
1162
1167
1168
SO3 symmetric stretching
1031
1031
1031
1031
1030
C–N deformation
851
851
850
849
847
CF3 asymmetric bending
756
756
756
757
760
SO3 symmetric bending
640
638
638
638
638
C-H out-plane deformation
624
624
624
624
624
CF3 symmetric bending
574
573
573
574
574
SO3 asymmetric bending
518
518
518
518
517
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Table S2 Ea calculated from Arrhenius and Vogel-Tamman-Fulcher (VTF) plot 1mol/L 0.5mol/L
0.1mol/L
0.05mol/L [BMIM]OTF
Ea calculated from Arrhenius plot
34 kJ
33 kJ
31 kJ
28 kJ
30 kJ
Ea calculated from VTF plot
622 K
573 K
534 K
492 K
523 K
100
Efficiency /%
80 60 40 0.1mol/L 0.5mol/L 1mol/L
20 0
0
5
10
15
20
Cycle number Figure S1 Coulombic efficiency of rechargeable aluminum batteries with using
-Z"/ohm
Al(OTF)3/[BMIM]OTF ionic liquids. 1.6x10
5
1.2x10
5
8.0x10
4
4.0x10
4
Before cycle After 5th cycle
0.0 0.0
4.0x10
4
8.0x10
4
1.2x10
5
1.6x10
5
Z'/ohm Figure S2 Electrochemical Impedance Spectra (EIS) of rechargeable aluminum battery with 0.5 mol/L Al(OTF)3/[BMIM]OTF ionic liquid electrolyte before and after cycles S-5
0.4
(b)3.0
0.3
2.5
Voltage /V
Capacity /mAhg
-1
(a)
0.2 0.1 0.0 -0.1
2.0 1st 2nd 3rd
1.5 1.0 0.5
0
20
40
60
Cycle number
80
100
0.0
0.1
0.2
0.3
0.4
0.5
0.6
-1
Capacity /mAhg
Figure S3 (a) Cycling performance; (b) Charge/discharge profiles of rechargeable aluminum battery using 0.5M Al(OTF)3/[BMIM]OTF ionic liquid electrolyte and untreated Al anode
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Beijing Key Laboratory of Environmental Science and Engineering, School of Materials
Science & Engineering, Beijing Institute of Technology, Beijing 100081, China ‡Collaborative Innovation Center of Electric Vehicles in Beijing, Beijing 100081, China
** Corresponding Authors: (Ying Bai) E-mail: [email protected] (Chuan Wu) E-mail: [email protected]
S-1
Experiment Details: The reagents were obtained from commercial sources and used without further purification. [BMIM]OTF (99%) was bought from Shanghai Jie Cheng Chemical Co., Ltd. The Al(OTF)3 was bought from Alfa Aesar. The preparation of Al(OTF)3/[BMIM]OTF ionic liquid was performed in a glove box filled with inert gas Ar. Al(OTF)3 was added to the [BMIM]OTF ionic liquid under stirring at a series molar concentration (0, 0.05, 0.1, 0.5, 1mol/L). Infrared spectra of ionic liquids were obtained with a Nicolet iS10 Fourier Transform Infrared Spectroscopy (FTIR) spectrometer at 4 cm-1 resolution. Cyclic Voltammetry (CV) and ionic conductivity were both measured on CHI604D electrochemical workstation. In CV measurement, the glassy carbon (GC) disk electrode (diameter 2mm) was used as working electrode, Al metal was used as the counter electrode and reference electrode, and the scan rate is 10mV/s. In ionic conductivity test, a DJS-1 type conductivity electrode was used. V2O5 nanowire was synthesized similar to the method used previously. 0.364 g V2O5 and 5 mL 30wt% H2O2 were added to 30 mL water and magnetically stirred for 0.5h. Then, the prepared solution was transferred to a polytetrafluoroethene-lined stainless steel reactor and heated for four days at 205 ºC. Finally, the prepared product was taken out and washing with deionized water for several times. After 60 ºC vacuum drying for 24h, it is calcinated at 500 ºC for 4 hours in air to get the final product. Rechargeable aluminum battery (2025 coin-type cells) using Al(OTF)3/ [BMIM]OTF ionic liquid as electrolyte was assembled in an argon-filled glove box. The cathode was made with V2O5 nanowire: Super P: PTFE binder=8:1:1 (mass ratio) coated on Al foam. Whatman glass
S-2
fiber (GF/C) was selected as the separator, and Al metal foil (99.9999% Al purity) was used as the anode. Al anode is treated by immersing in AlCl3/[BMIM]Cl=1.1:1 ionic liquids for 24 hours, then it was taken out, washed with ethanol and dry. All Al treatment procedures are performed in glove box. AlCl3/[BMIM]Cl=1.1:1 ionic liquid was prepared by mixing AlCl3 with [BMIM]Cl according to molar ratio, then stirred overnight until homogeneous and clear liquid obtained. Galvanostatic charge–discharge test was performed on a LAND CT2001A battery tester in a potential range of 3–0.02 V, at the current density of 10 mA/g.
S-3
Table S1. Frequencies and assignments of vibrations in Figure 1 [BMIM]OTF
0.05 mol/L
0.1 mol/L
0.5 mol/L
1 mol/L
(cm-1)
(cm-1)
(cm-1)
(cm-1)
(cm-1)
C4,5-H stretching
3154
3154
3154
3155
3156
C2-H stretching
3115
3115
3115
3116
3118
CH3 asymmetric stretching
2966
2966
2966
2967
2968
CH2 asymmetric stretching
2939
2939
2939
2940
2941
CH3 symmetric stretching
2878
2878
2878
2879
2880
C=N stretching
1575
1575
1575
1575
1575
CH3 asymmetric bending
1468
1468
1468
1467
1467
CH2 in-plane bending
1432
1432
1432
1431
1431
CH3 symmetric bending
1386
1386
1386
1386
1386
SO3 asymmetric stretching
1262
1262
1261
1261
1289
SO3 symmetric stretching
1225
1225
1225
1226
1227
CF3 asymmetric stretching
1162
1162
1162
1167
1168
SO3 symmetric stretching
1031
1031
1031
1031
1030
C–N deformation
851
851
850
849
847
CF3 asymmetric bending
756
756
756
757
760
SO3 symmetric bending
640
638
638
638
638
C-H out-plane deformation
624
624
624
624
624
CF3 symmetric bending
574
573
573
574
574
SO3 asymmetric bending
518
518
518
518
517
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Table S2 Ea calculated from Arrhenius and Vogel-Tamman-Fulcher (VTF) plot 1mol/L 0.5mol/L
0.1mol/L
0.05mol/L [BMIM]OTF
Ea calculated from Arrhenius plot
34 kJ
33 kJ
31 kJ
28 kJ
30 kJ
Ea calculated from VTF plot
622 K
573 K
534 K
492 K
523 K
100
Efficiency /%
80 60 40 0.1mol/L 0.5mol/L 1mol/L
20 0
0
5
10
15
20
Cycle number Figure S1 Coulombic efficiency of rechargeable aluminum batteries with using
-Z"/ohm
Al(OTF)3/[BMIM]OTF ionic liquids. 1.6x10
5
1.2x10
5
8.0x10
4
4.0x10
4
Before cycle After 5th cycle
0.0 0.0
4.0x10
4
8.0x10
4
1.2x10
5
1.6x10
5
Z'/ohm Figure S2 Electrochemical Impedance Spectra (EIS) of rechargeable aluminum battery with 0.5 mol/L Al(OTF)3/[BMIM]OTF ionic liquid electrolyte before and after cycles S-5
0.4
(b)3.0
0.3
2.5
Voltage /V
Capacity /mAhg
-1
(a)
0.2 0.1 0.0 -0.1
2.0 1st 2nd 3rd
1.5 1.0 0.5
0
20
40
60
Cycle number
80
100
0.0
0.1
0.2
0.3
0.4
0.5
0.6
-1
Capacity /mAhg
Figure S3 (a) Cycling performance; (b) Charge/discharge profiles of rechargeable aluminum battery using 0.5M Al(OTF)3/[BMIM]OTF ionic liquid electrolyte and untreated Al anode
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