Supporting Information
Supporting Information
Iron Telluride Decorated Reduced Graphene Oxide Hybrid Microspheres as Anode Materials with Improved Na-Ion Storage Properties
Jung Sang Cho1, Seung Yeon Lee1, Jung-Kul Lee2,*, and Yun Chan Kang1,*
Address: 1
Department of Materials Science and Engineering, Korea University, Anam-Dong,
Seongbuk-Gu, Seoul 136-713, Republic of Korea. 2
Department of Chemical Engineering, Konkuk University, 1 Hwayang-dong, Gwangjin-gu,
Seoul 143-701, Republic of Korea.
*Corresponding author. E-mail: [email protected], [email protected].
S-1
Characterization The crystal structures of the FeTe2-rGO hybrid and bare FeTe2 powders were investigated using X-ray diffractometry (XRD, X’pert PRO MPD) with Cu-Kα radiation (λ = 1.5418 Å) at the Korea Basic Science Institute (Daegu). The morphologies of the two samples were investigated using scanning electron microscopy (SEM, TESCAN, VEGA3 SBH) and highresolution transmission electron microscopy (HR-TEM, JEOL, JEM-2100F) at a working voltage of 200 kV. The specific surface areas of the powders before and after post-treatment at various temperatures were calculated by a Brunauer-Emmett-Teller analysis of nitrogenadsorption (TriStar 3000). X-ray photoelectron spectroscopy (XPS, Thermo Scientific KAlpha) of the powders was performed with Al Kα radiation (1486.6 eV). The structure of the carbon in the microspheres was characterized via Raman spectroscopy (Jobin Yvon LabRam HR800, excitation source: 632.8 nm He-Ne laser) at room temperature. To determine the amount of rGO in the FeTe2-rGO hybrid powders, thermogravimetric analysis (TGA, TA Instruments, SDT Q600) and elemental analysis (EA, Eurovector, EA3000) was performed in air at a heating rate of 10 °C min-1.
Electrochemical measurements The electrochemical properties of the FeTe2-rGO hybrid and bare FeTe2 powders were analyzed using a 2032-type coin cell. The anode was prepared by mixing the active material, carbon black, and sodium carboxymethyl cellulose at a weight ratio of 7:2:1. Na metal and microporous polypropylene film were used as the counter electrode and the separator, respectively. The electrolyte was 1 M NaClO4 and 5% fluoroethylene carbonate dissolved in a mixture of ethylene carbonate/dimethyl carbonate (1:1 v/v). The discharge/charge characteristics of the samples were investigated by cycling over a potential range of 0.001–3.0 V at various current densities. Cyclic voltammograms (CVs) were measured at a scan rate of 0.07 mV s-1. The size of the negative electrode containing the FeTe2 powders was 1.0 cm × 1.0 cm and the mass loading was approximately 2.0 mg cm-2. The electrode density of the FeTe2-decorated rGO hybrid powders was approximately 1.62 g cm-3. Electrochemical impedance spectra were obtained by AC electrochemical impedance spectroscopy (EIS, eDAQ SP1 ZIVE Potentiostat) over a frequency range of 0.01 Hz–1000 kHz.
S-2
Figure S1. Schematic diagram of the spray pyrolysis applied in the preparation of the Fe3O4decorated rGO hybrid powders as a precursor powder.
S-3
Figure S2. (a) Schematic diagram and (b) digital photo of the pilot-scale spray drying system applied in the preparation of the precursor powders for the bare Fe2O3 powders.
S-4
Figure S3. Morphologies and phase analysis of the Fe3O4-decorated rGO hybrid powders prepared at 600 oC in Ar atmosphere by spray pyrolysis: (a) SEM image, (b-d) TEM images, (e) HR-TEM image, and (f) XRD pattern.
S-5
Figure S4. TG analysis of the FeTe2-decorated rGO hybrid powders.
Table S1. Elemental analysis of the FeTe2-decorated rGO hybrid powders.
S-6
Figure S5. SEM images and XRD patterns of the bare FeTe2 powders prepared (a) after spray drying process, (b) subsequent combustion process for the sake of carbon decomposition in the structure, and (c) subsequent tellurization process.
S-7
Re : the electrolyte resistance, corresponding to the intercept of high frequency semicircle at Zre axis Rf : the SEI layer resistance corresponding to the high-frequency semicircle Q1 : the dielectric relaxation capacitance corresponding to the high-frequency semicircle Rct: the denote the charger transfer resistance related to the middle-frequency semicircle Q2 : the associated double-layer capacitance related to the middle-frequency semicircle Zw : the Na-ion diffusion resistance
Figure S6. Randle-type equivalent circuit model used for AC impedance fitting.
S-8
Figure S7. CV curves of the bare FeTe2 powders.
S-9
Table S2. Sodium-ion storage properties of various metal compounds materials. Materials
Voltage range (V)
Current rate
Initial Coulombic efficiency [%]
Initial discharge/charge Capacity
FeTe2-rGO composite
0.001-3.0
0.2 A g-1
76 %
493/373 mAh g-1
293 mAh g-1
80
This work
SnS2-rGO composite
0.01-2.5
75 %
839/630 mAh g-1
628 mAh g-1
100
S1
CuO nanorod arrays
0-3.0
~88 %
~700/~620 mAh g-1
290 mA h g-1
450
S2
TiO2 nanotube
0.9-2.5
0.05 A g-1
68 %
110/75 mAh g-1
150 mAh g-1
15
S3
MoS2/graphene composite
0.01-2.0
0.025 A g-1
83 %
407/338 mAh g-1
-
20
S4
SnSe/carbon nanocomposite
0.01-2.0
0.5 A g-1
55.1 %
748/412 mAh g-1
325 mAh g-1
200
S5
MoSe2 yolk-shell
0.001-3.0
0.2 A g-1
85 %
527/448 mAh g-1
433 mAh g-1
50
S6
Sn4P3
0-1.5
0.1 A g-1
-
-
718 mAh g-1
100
S7
FeSe2 microspheres
0.5-2.9
1 A g-1
-
442/mAh g-1
372 mAh g-1
2000
S8
Flower-like Sb2S3
0.01-2.0
0.05 A g-1
72.9
970/707 mAh g-1
835 mAh g-1
50
S9
0.2 A g1
0.2 A g1
Final discharge capacity
Cycle number
Ref
MnS hollow microspheres VS4/rGO composite powder NiS2-graphene nanosheets
0.01-2.6
0.1 A g-1
~65 %
~750/~490 mAh g-1
308 mAh g-1
125
S10
0.01-2.2
0.1 A g-1
75 %
450/338 mAhg-1
241 mAh g-1
50
S11
-
0.1 C
65 %
529/mAh g-1
407 mAh g-1
50
S12
Cu3P nanowire
0.01-2.5
1 A g-1
-
-/196 mAh g-1
134 mAh g-1
260
S13
0.001-3.0
0.3 A g-1
70 %
656/460 mAh g-1
420 mAh g-1
50
S14
0.001-3.0
0.2 A g-1
72 %
717/516 mAh g-1
468 mAh g-1
100
S15
0-2.0
0.143 A g-1
-
-
707 mAh g-1
50
S16
CoSex-rGO composite NiSe2/C porous nanofiber SnSe alloy
Reference (S1)
Qu, B.; Ma, C.; Ji, G.; Xu, C., Xu, J.; Meng, Y. S.; Wang, T.; Lee, J. Y. Layered SnS2‐
Reduced Graphene Oxide Composite–A High‐Capacity, High‐Rate, and Long‐Cycle Life Sodium‐Ion Battery Anode Material. Adv. Mater. 2014, 26, 3854-3859. (S2)
Yuan, S.; Huang, X. L.; Ma, D. L.; Wang, H. G.; Meng, F. Z.; Zhang, X. B.
Engraving Copper Foil to Give Large‐Scale Binder‐Free Porous CuO Arrays for a High‐ Performance Sodium‐Ion Battery Anode. Adv. Mater. 2014, 26, 2273-2279. S-10
(S3)
Xiong, H.; Slater, M. D.; Balasubramanian, M.; Johnson, C. S.; Rajh, T. Amorphous
TiO2 Nanotube Anode for Rechargeable Sodium Ion Batteries. J.Phys.Chem. Lett. 2011, 2, 2560-2565. (S4)
David, L.; Bhandavat, R.; Singh, G. MoS2/Graphene Composite Paper for Sodium-Ion
Battery Electrodes. ACS nano 2014, 8, 1759-1770. (S5)
Zhang, Z.; Zhao, X.; Li, J. SnSe/Carbon Nanocomposite Synthesized by High Energy
Ball Milling as an Anode Material for Sodium-Ion and Lithium-Ion Batteries. Electrochim.
Acta 2015, 176, 1296-1301. (S6)
Ko, Y. N.; Choi, S. H.; Park, S. B.; Kang, Y. C. Hierarchical MoSe2 Yolk–Shell
Microspheres with Superior Na-Ion Storage Properties. Nanoscale 2014, 6, 10511-10515. (S7)
Kim, Y. J.; Kim, Y.; Choi, A.; Woo, S.; Mok, D.; Choi, N.-S.; Jung, Y. S.; Ryu, J. H.;
Oh, S. M.; Lee, K. T. Tin Phosphide as a Promising Anode Material for Na-Ion Batteries. Adv.
Mater. 2014, 26, 4139-4144. (S8)
Zhang, K.; Hu, Z.; Liu, X.; Tao, Z.; Chen, J. FeSe2 Microspheres as a High‐
Performance Anode Material for Na‐Ion Batteries. Adv. Mater. 2015, 27, 3305-3309. (S9)
Zhu, Y.; Nie, P.; Shen, L.; Dong, S.; Sheng, Q.; Li, H.; Luo H.; Zhang, X. High Rate
Capability and Superior Cycle Stability of a Flower-Like Sb2S3 Anode for High-Capacity Sodium Ion Batteries. Nanoscale 2015, 7, 3309-3315. (S10) Xu, X.; Ji, S.; Gu, M.; Liu, J. In Situ Synthesis of MnS Hollow Microspheres on Reduced Graphene Oxide Sheets as High-Capacity and Long-Life Anodes for Li-and Na-Ion Batteries. ACS Appl. Mater. Interfaces 2015, 7, 20957-20964. (S11) Sun, R.; Wei, Q.; Li, Q.; Luo, W.; An, Q.; Sheng, J.; Wang, D.; Chen, W.; Mai, L. Vanadium Sulfide on Reduced Graphene Oxide Layer as a Promising Anode for Sodium Ion Battery. ACS Appl. Mater. Interfaces 2015, 7, 20902-20908. (S12) Wang, T.; Hu, P.; Zhang, C.; Du, H.; Zhang, Z.; Wang, X.; Chen, S.; Xiong, J.; Cui, G. Nickel Disulfide–Graphene Nanosheets Composites with Improved Electrochemical Performance for Sodium Ion Battery. ACS Appl. Mater. Interfaces 2016, 8, 7811-7817.
S-11
(S13) Fan, M.; Chen, Y.; Xie, Y.; Yang, T.; Shen, X.; Xu, N.; Yu, H.; Yan, C. Half‐Cell and Full‐Cell Applications of Highly Stable and Binder‐Free Sodium Ion Batteries Based on Cu3P Nanowire Anodes. Adv. Funct. Mater. 2016, DOI: 10.1002/adfm.201601323. (S14) Park, G. D.; Kang, Y. C. One‐Pot Synthesis of CoSex–rGO Composite Powders by Spray Pyrolysis and Their Application as Anode Material for Sodium‐Ion Batteries. Chem.
Eur. J. 2016, 22, 4140-4146. (S15) Cho, J. S.; Lee, S. Y.; Kang, Y. C. First Introduction of NiSe2 to Anode Material for Sodium-Ion Batteries: A Hybrid of Graphene-Wrapped NiSe2/C Porous Nanofiber. Sci.
Rep. 6 2016, 23338 (S16) Kim, Y.; Kim, Y.; Park, Y.; Jo, Y. N.; Kim, Y. J.; Choi, N. S.; Lee, K. T. SnSe Alloy as a Promising Anode Material for Na-Ion Batteries. Chem. Commun. 2015, 51, 50-53.
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Iron Telluride Decorated Reduced Graphene Oxide Hybrid Microspheres as Anode Materials with Improved Na-Ion Storage Properties
Jung Sang Cho1, Seung Yeon Lee1, Jung-Kul Lee2,*, and Yun Chan Kang1,*
Address: 1
Department of Materials Science and Engineering, Korea University, Anam-Dong,
Seongbuk-Gu, Seoul 136-713, Republic of Korea. 2
Department of Chemical Engineering, Konkuk University, 1 Hwayang-dong, Gwangjin-gu,
Seoul 143-701, Republic of Korea.
*Corresponding author. E-mail: [email protected], [email protected].
S-1
Characterization The crystal structures of the FeTe2-rGO hybrid and bare FeTe2 powders were investigated using X-ray diffractometry (XRD, X’pert PRO MPD) with Cu-Kα radiation (λ = 1.5418 Å) at the Korea Basic Science Institute (Daegu). The morphologies of the two samples were investigated using scanning electron microscopy (SEM, TESCAN, VEGA3 SBH) and highresolution transmission electron microscopy (HR-TEM, JEOL, JEM-2100F) at a working voltage of 200 kV. The specific surface areas of the powders before and after post-treatment at various temperatures were calculated by a Brunauer-Emmett-Teller analysis of nitrogenadsorption (TriStar 3000). X-ray photoelectron spectroscopy (XPS, Thermo Scientific KAlpha) of the powders was performed with Al Kα radiation (1486.6 eV). The structure of the carbon in the microspheres was characterized via Raman spectroscopy (Jobin Yvon LabRam HR800, excitation source: 632.8 nm He-Ne laser) at room temperature. To determine the amount of rGO in the FeTe2-rGO hybrid powders, thermogravimetric analysis (TGA, TA Instruments, SDT Q600) and elemental analysis (EA, Eurovector, EA3000) was performed in air at a heating rate of 10 °C min-1.
Electrochemical measurements The electrochemical properties of the FeTe2-rGO hybrid and bare FeTe2 powders were analyzed using a 2032-type coin cell. The anode was prepared by mixing the active material, carbon black, and sodium carboxymethyl cellulose at a weight ratio of 7:2:1. Na metal and microporous polypropylene film were used as the counter electrode and the separator, respectively. The electrolyte was 1 M NaClO4 and 5% fluoroethylene carbonate dissolved in a mixture of ethylene carbonate/dimethyl carbonate (1:1 v/v). The discharge/charge characteristics of the samples were investigated by cycling over a potential range of 0.001–3.0 V at various current densities. Cyclic voltammograms (CVs) were measured at a scan rate of 0.07 mV s-1. The size of the negative electrode containing the FeTe2 powders was 1.0 cm × 1.0 cm and the mass loading was approximately 2.0 mg cm-2. The electrode density of the FeTe2-decorated rGO hybrid powders was approximately 1.62 g cm-3. Electrochemical impedance spectra were obtained by AC electrochemical impedance spectroscopy (EIS, eDAQ SP1 ZIVE Potentiostat) over a frequency range of 0.01 Hz–1000 kHz.
S-2
Figure S1. Schematic diagram of the spray pyrolysis applied in the preparation of the Fe3O4decorated rGO hybrid powders as a precursor powder.
S-3
Figure S2. (a) Schematic diagram and (b) digital photo of the pilot-scale spray drying system applied in the preparation of the precursor powders for the bare Fe2O3 powders.
S-4
Figure S3. Morphologies and phase analysis of the Fe3O4-decorated rGO hybrid powders prepared at 600 oC in Ar atmosphere by spray pyrolysis: (a) SEM image, (b-d) TEM images, (e) HR-TEM image, and (f) XRD pattern.
S-5
Figure S4. TG analysis of the FeTe2-decorated rGO hybrid powders.
Table S1. Elemental analysis of the FeTe2-decorated rGO hybrid powders.
S-6
Figure S5. SEM images and XRD patterns of the bare FeTe2 powders prepared (a) after spray drying process, (b) subsequent combustion process for the sake of carbon decomposition in the structure, and (c) subsequent tellurization process.
S-7
Re : the electrolyte resistance, corresponding to the intercept of high frequency semicircle at Zre axis Rf : the SEI layer resistance corresponding to the high-frequency semicircle Q1 : the dielectric relaxation capacitance corresponding to the high-frequency semicircle Rct: the denote the charger transfer resistance related to the middle-frequency semicircle Q2 : the associated double-layer capacitance related to the middle-frequency semicircle Zw : the Na-ion diffusion resistance
Figure S6. Randle-type equivalent circuit model used for AC impedance fitting.
S-8
Figure S7. CV curves of the bare FeTe2 powders.
S-9
Table S2. Sodium-ion storage properties of various metal compounds materials. Materials
Voltage range (V)
Current rate
Initial Coulombic efficiency [%]
Initial discharge/charge Capacity
FeTe2-rGO composite
0.001-3.0
0.2 A g-1
76 %
493/373 mAh g-1
293 mAh g-1
80
This work
SnS2-rGO composite
0.01-2.5
75 %
839/630 mAh g-1
628 mAh g-1
100
S1
CuO nanorod arrays
0-3.0
~88 %
~700/~620 mAh g-1
290 mA h g-1
450
S2
TiO2 nanotube
0.9-2.5
0.05 A g-1
68 %
110/75 mAh g-1
150 mAh g-1
15
S3
MoS2/graphene composite
0.01-2.0
0.025 A g-1
83 %
407/338 mAh g-1
-
20
S4
SnSe/carbon nanocomposite
0.01-2.0
0.5 A g-1
55.1 %
748/412 mAh g-1
325 mAh g-1
200
S5
MoSe2 yolk-shell
0.001-3.0
0.2 A g-1
85 %
527/448 mAh g-1
433 mAh g-1
50
S6
Sn4P3
0-1.5
0.1 A g-1
-
-
718 mAh g-1
100
S7
FeSe2 microspheres
0.5-2.9
1 A g-1
-
442/mAh g-1
372 mAh g-1
2000
S8
Flower-like Sb2S3
0.01-2.0
0.05 A g-1
72.9
970/707 mAh g-1
835 mAh g-1
50
S9
0.2 A g1
0.2 A g1
Final discharge capacity
Cycle number
Ref
MnS hollow microspheres VS4/rGO composite powder NiS2-graphene nanosheets
0.01-2.6
0.1 A g-1
~65 %
~750/~490 mAh g-1
308 mAh g-1
125
S10
0.01-2.2
0.1 A g-1
75 %
450/338 mAhg-1
241 mAh g-1
50
S11
-
0.1 C
65 %
529/mAh g-1
407 mAh g-1
50
S12
Cu3P nanowire
0.01-2.5
1 A g-1
-
-/196 mAh g-1
134 mAh g-1
260
S13
0.001-3.0
0.3 A g-1
70 %
656/460 mAh g-1
420 mAh g-1
50
S14
0.001-3.0
0.2 A g-1
72 %
717/516 mAh g-1
468 mAh g-1
100
S15
0-2.0
0.143 A g-1
-
-
707 mAh g-1
50
S16
CoSex-rGO composite NiSe2/C porous nanofiber SnSe alloy
Reference (S1)
Qu, B.; Ma, C.; Ji, G.; Xu, C., Xu, J.; Meng, Y. S.; Wang, T.; Lee, J. Y. Layered SnS2‐
Reduced Graphene Oxide Composite–A High‐Capacity, High‐Rate, and Long‐Cycle Life Sodium‐Ion Battery Anode Material. Adv. Mater. 2014, 26, 3854-3859. (S2)
Yuan, S.; Huang, X. L.; Ma, D. L.; Wang, H. G.; Meng, F. Z.; Zhang, X. B.
Engraving Copper Foil to Give Large‐Scale Binder‐Free Porous CuO Arrays for a High‐ Performance Sodium‐Ion Battery Anode. Adv. Mater. 2014, 26, 2273-2279. S-10
(S3)
Xiong, H.; Slater, M. D.; Balasubramanian, M.; Johnson, C. S.; Rajh, T. Amorphous
TiO2 Nanotube Anode for Rechargeable Sodium Ion Batteries. J.Phys.Chem. Lett. 2011, 2, 2560-2565. (S4)
David, L.; Bhandavat, R.; Singh, G. MoS2/Graphene Composite Paper for Sodium-Ion
Battery Electrodes. ACS nano 2014, 8, 1759-1770. (S5)
Zhang, Z.; Zhao, X.; Li, J. SnSe/Carbon Nanocomposite Synthesized by High Energy
Ball Milling as an Anode Material for Sodium-Ion and Lithium-Ion Batteries. Electrochim.
Acta 2015, 176, 1296-1301. (S6)
Ko, Y. N.; Choi, S. H.; Park, S. B.; Kang, Y. C. Hierarchical MoSe2 Yolk–Shell
Microspheres with Superior Na-Ion Storage Properties. Nanoscale 2014, 6, 10511-10515. (S7)
Kim, Y. J.; Kim, Y.; Choi, A.; Woo, S.; Mok, D.; Choi, N.-S.; Jung, Y. S.; Ryu, J. H.;
Oh, S. M.; Lee, K. T. Tin Phosphide as a Promising Anode Material for Na-Ion Batteries. Adv.
Mater. 2014, 26, 4139-4144. (S8)
Zhang, K.; Hu, Z.; Liu, X.; Tao, Z.; Chen, J. FeSe2 Microspheres as a High‐
Performance Anode Material for Na‐Ion Batteries. Adv. Mater. 2015, 27, 3305-3309. (S9)
Zhu, Y.; Nie, P.; Shen, L.; Dong, S.; Sheng, Q.; Li, H.; Luo H.; Zhang, X. High Rate
Capability and Superior Cycle Stability of a Flower-Like Sb2S3 Anode for High-Capacity Sodium Ion Batteries. Nanoscale 2015, 7, 3309-3315. (S10) Xu, X.; Ji, S.; Gu, M.; Liu, J. In Situ Synthesis of MnS Hollow Microspheres on Reduced Graphene Oxide Sheets as High-Capacity and Long-Life Anodes for Li-and Na-Ion Batteries. ACS Appl. Mater. Interfaces 2015, 7, 20957-20964. (S11) Sun, R.; Wei, Q.; Li, Q.; Luo, W.; An, Q.; Sheng, J.; Wang, D.; Chen, W.; Mai, L. Vanadium Sulfide on Reduced Graphene Oxide Layer as a Promising Anode for Sodium Ion Battery. ACS Appl. Mater. Interfaces 2015, 7, 20902-20908. (S12) Wang, T.; Hu, P.; Zhang, C.; Du, H.; Zhang, Z.; Wang, X.; Chen, S.; Xiong, J.; Cui, G. Nickel Disulfide–Graphene Nanosheets Composites with Improved Electrochemical Performance for Sodium Ion Battery. ACS Appl. Mater. Interfaces 2016, 8, 7811-7817.
S-11
(S13) Fan, M.; Chen, Y.; Xie, Y.; Yang, T.; Shen, X.; Xu, N.; Yu, H.; Yan, C. Half‐Cell and Full‐Cell Applications of Highly Stable and Binder‐Free Sodium Ion Batteries Based on Cu3P Nanowire Anodes. Adv. Funct. Mater. 2016, DOI: 10.1002/adfm.201601323. (S14) Park, G. D.; Kang, Y. C. One‐Pot Synthesis of CoSex–rGO Composite Powders by Spray Pyrolysis and Their Application as Anode Material for Sodium‐Ion Batteries. Chem.
Eur. J. 2016, 22, 4140-4146. (S15) Cho, J. S.; Lee, S. Y.; Kang, Y. C. First Introduction of NiSe2 to Anode Material for Sodium-Ion Batteries: A Hybrid of Graphene-Wrapped NiSe2/C Porous Nanofiber. Sci.
Rep. 6 2016, 23338 (S16) Kim, Y.; Kim, Y.; Park, Y.; Jo, Y. N.; Kim, Y. J.; Choi, N. S.; Lee, K. T. SnSe Alloy as a Promising Anode Material for Na-Ion Batteries. Chem. Commun. 2015, 51, 50-53.
S-12
