Urchin-like V 2 O 3 /C Hollow Nanospheres Hybrid for High-Capacity and Long-Cycle-Life Lithium Storage

Transcription

1 Supporting Information Urchin-like V 2 O 3 /C Hollow Nanospheres Hybrid for High-Capacity and Long-Cycle-Life Lithium Storage Peng Yu, Xu Liu, Lei Wang,* Chungui Tian, Haitao Yu, and Honggang Fu* Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education of the People s Republic of China, Heilongjiang University, Harbin, Xuefu Road, , P. R. China fuhg@vip.sina.com, fuhg@hlju.edu.cn, wanglei0525@126.com. Page S1-S20 Contents: S1.Figure S1. EDX mapping of the V 2 O 3 /C precursor S2.Figure S2. SEM images of V 2 O 3 /C hybrid with large scale scan of 5um. S3.Figure S3. HRTEM images of V 2 O 3 /C. S4.Figure S4. (a) SEM image of VO x rods and (b) the corresponding magnified image. S5.Figure S5. SEM image of the as synthesized carbon spheres.

2 S6.Figure S6. Nitrogen adsorption/desorption isotherm of V 2 O 3 /C hollow sphere hybrid and VO x rod. S7.Figure S7. TG curve of the V 2 O 3 /C hybrid measured in air. S8.Figure S8. EDX analysis of V 2 O 3 /C hybrid. S9.Figure S9. Wide spread XPS spectrum of the V 2 O 3 /C hybrid. S10.Figure S10. XRD patterns of the precursors synthesized by different solvothermal time (5min, 0.5 h, 2h and 24h). S11.Figure S11. FT-IR spectra of the precursors synthesized by different solvothermal time (5min, 0.5 h, 2h and 24h). As compared, the corresponding spectra about V 2 O 3 /C and carbon sphere were also provided. S12.Figure S12. SEM images of the precursors synthesized by different solvothermal time: (a)5 min, (b) 0.5 h, (c) 2h and (d) 24 h. S13.Figure S13. SEM images of the V 2 O 3 /C composites synthesized derived from different usage amount of glucose: (a, b) 0.1 mmol, (c, d) 0.5 mmol, (e, f) 2 mmol and (g, h) 5 mmol. S14.Figure S14. TEM images of V 2 O 3 /C hybrids with different thermal treatment time: (a, b) 30min and (c, d) 1h. S15.Figure S15. Rate performances of V 2 O 3 /C-1 and V 2 O 3 /C-2 electrode, respectively. S16.Figure S16. SEM image of the V 2 O 3 /C hybrid electrode after 1000 cycles. S17.Figure S17. Schematic of (A) V 2 O 3 hollow nanospheres and (B) VO x nanorods during lithiation and delithiation. S18.Figure S18. Charge and discharge profile of the LiMn 1/3 Co 1/3 Ni 1/3 O 2 electrode. S19.Table S1. A survey of electrochemical properties of various reported V 2 O 3 and its hybrid composites in lithium ion batteries.

3 Figure S1. EDX mapping of the V 2 O 3 /C precursor. S 1

4 Figure S2. SEM images of V 2 O 3 /C hybrid with large scale scan of 5um. As is shown in Figure S2, the V 2 O 3 /C nanospheres were homogeneous and uniformly dispersed with a large scale scan of 5 um. S 2

5 Figure S3. HRTEM images of V 2 O 3 /C. S 3

6 Figure S4. (a) SEM image of VO x rods and (b) the corresponding magnified image. As it is shown in Figure S4, when ammonium metavanadate was as the unique raw material, VO x rods about 500 nm thickness and 5-10 µm length instead of spheres morphology can be obtained. S 4

7 Figure S5. SEM image of the as synthesized carbon spheres. As shown in Figure S5, carbonaceous spheres obtained through the solvothermal reaction of glucose, indicating that glucose is served as the structural direction agent for the formation of spherical hybrid nanostructures. S 5

8 Figure S6. Nitrogen adsorption/desorption isotherm of V 2 O 3 /C hollow sphere hybrid and VO x rod. As is shown in Figure S6, the BET surface area of V 2 O 3 /C hollow nanospheres hybrid and VO x rods are m 2 /g and 3.5 m 2 /g, respectively. The high BET surface area of V 2 O 3 /C hollow nanospheres hybrid can be attributed to the overlap of the nanothrons on the surface shell of nanospheres. S 6

9 Figure S7. TG curve of the V 2 O 3 /C hybrid measured in air. Thermogravimetric (TG) analysis was carried out in air. With the temperature increasing, carbon component and V 2 O 3 gradually transformed into CO 2 and V 2 O 5, respectively. Based on the eventual product was V 2 O 5, the carbon content calculated in V 2 O 3 /C hollow nanospheres is about 16.9%, corresponding to a V 2 O 3 content of 83.1%. S 7

10 Figure S8. EDX analysis of V 2 O 3 /C hybrid. As is shown in Figure S8, the EDX spectrum shows the atom percentages of V, C and O in V 2 O 3 /C hybrid are about 21.8, 40.1 and 38.1 %, respectively. Therein, the carbon content is lower than that shown in TG, implying that more carbon component distributes on the peripheral of the nanostructure. S 8

11 Figure S9. Wide spread XPS spectrum of the V 2 O 3 /C hybrid. S 9

12 Figure S10. XRD patterns of the precursors synthesized by different solvothermal time (5min, 0.5 h, 2h and 24h). The characteristics of the precursors derived from different solvothermal time were analyzed. As the XRD patterns shown in Figure S10, after 0.5 h solvothermal reaction, the precursors convert into (NH 4 ) 1.92 V 3 O 8, and the valence of V remains +5. The valence of V in V 2 O 3 /C hybrid is +3, which is due to the carbon thermal reduction. S 1

13 Figure S11. FT-IR spectra of the precursors synthesized by different solvothermal time (5min, 0.5 h, 2h and 24h). As compared, the corresponding spectra about V 2 O 3 /C and carbon sphere were also provided. FT-IR spectra of the precursor at different solvothermal reaction time and V 2 O 3 /C hybrid were shown in Figure S11. For the V 2 O 3 /C precursor, absorption peaks at 2918 cm -1 and 2850 cm -1 can be observed, which are correspond to the stretching vibrations of -CH 3 and -CH 2 - groups, respectively. After calcination, the absorption peaks corresponding to -CH 3, -CH 2 - disappeared, indicating that the decrease of carbon component during calcination. In the spectrum of V 2 O 3 /C precursor, the absorption peaks in the range of cm -1 corresponds to stretch vibrations of V(V)=O, which disappeared after calcination. Additionally, a absorption peak for the V 2 O 3 /C at 982 cm -1 can be observed corresponds to the symmetric stretching vibration of V(III)=O, indicating the presence of V 2 O 3. It indicates that the precursor were transformed to V 2 O 3 by a carbon thermal reduction progress. S 1

14 Figure S12. SEM images of the precursors synthesized by different solvothermal time: (a)5 min, (b) 0.5 h, (c) 2h and (d) 24 h. It can be obviously observed that, the initial bulk structures were gradually transferred to nanospheres with the time increase of solvothermal reaction. As it is reported that glucose can form carbonaceous microspheres during the thermal reaction through the hydrolytic polymerization. With the reacting time increases to 6 h, a lot of nanospheres are obtained (Figure S6c). At last, uniform precursor with spherical structure are formed at 24 h (Figure 1a). S 1

15 Figure S13. SEM images of the V 2 O 3 /C composites synthesized derived from different usage amount of glucose: (a, b) 0.1 mmol, (c, d) 0.5 mmol, (e, f) 2 mmol and (g, h) 5 mmol. It can be observed that the sample composed both lamellar and spherical nanostructures when the amount of glucose is 0.1 mmol. With the increase of glucose amount, homogeneous spherical structure were formed gradually. When the amount of glucose is up to 10 mmol or more, the nanospheres become larger and inhomogeneous. It is demonstrated that the morderate usage amount of glucose is great imortant for the formation of spherical stuctures. S 1

16 Figure S14. TEM images of V 2 O 3 /C hybrids with different thermal treatment time: (a, b) 30min and (c, d) 1h. In order to explore whether hollow structure was formed during the thermal progress, precursor were treated with different calcination time. As it is shown in Figure S14, after 30 min calcination, the precursor still keep the spherical morphology, however, the surface is rougher and consists with a few nanoparticles. More importantly, some of the nanospheres already show a hollow structure with a relatively smaller cavity volume. With the calcining time lenthened to 1 h, it can be seen that cavity volume gradually increased, as with the amount of nanoparticles on the surface. Thus, it can be confirmed that the hollow structure is formed in the process of heat treatment, meanwhile the inner part of the precursor sphere gradually dissolved and diffused to the surface of the spherical structure to form urchin-like hollow nanospheres. S 1

17 Figure S15. Rate performances of V 2 O 3 /C-1 and V 2 O 3 /C-2 electrode, respectively. As it is shown in Figure S15, the V 2 O 3 /C-1 and V 2 O 3 /C-2 exhibit lower capacity than V 2 O 3 /C, indicating that the morphology of uniform nanosphere may attributes to better performance. S 1

18 Figure S16. SEM image of the V 2 O 3 /C hybrid electrode after 1000 cycles. The SEM image of the V 2 O 3 /C electrode after 1000 cycles is shown in Figure S16. Although the nanospheres turned to be a little more nonuniform, the spherical structure was seen to be retained after the repeated lithiation/delithiation, such good structural stability ensured the prolonged cycling stability. S 1

19 Figure S17. Schematic of (A) V 2 O 3 hollow nanospheres and (B) VO x nanorods during lithiation and delithiation. Schematic illustration of the lithiation / delithiation process for V 2 O 3 /C composite and VO x nanorods are shown in Figure S17. During the lithiation and delithiation progress, the VO x nanorods may suffer from the collapse of the structure and self-aggregation, which may induce poor cycle performance. While for the V 2 O 3 /C hollow spheres, the Li + can embed into peripheral lamellar structures of the V 2 O 3 hollow nanosphere, which are connected to the hollow spherical shell. The crossing and overlapped lamellar structure can buffer the volume variation during the consecutive lithiation and delithiation process. Meanwhile, the void formed from the overlapping lamellar structure are favourable for the infiltrating of the electrolyte and fast transfer of lithium ion and electron S 1

20 Figure S18. Charge and discharge profile of the LiMn 1/3 Co 1/3 Ni 1/3 O 2 electrode. The cathode LiMn 1/3 Co 1/3 Ni 1/3 O 2 electrode electrode was evaluated in the voltage range of V shown in Figure S18, the corresponding charge and discharge capacity are 348 and 382 mah g -1. S 1

21 Table S1 A survey of electrochemical properties of various reported V 2 O 3 and its hybrid composites in lithium ion batteries. Synthesis Reaction Electrodes electrochemical properties ref. method Temperature V 2 O 3 /C Solvothermal 1320 at 1 A g 1 This 180 o C Hollow sphere method after 1000 cycle work Mesoporous Templatel 541 mah g -1 at 0.1 A g V 2 O 3 -OMC method after 10 cycle Reduction of 750mAh g 1 at 0.2 A g -1 V 2 O 3 /C 200 o C 2 V 2 O 5 after 100 cycle C- V 2 O 3 Nanowire Reduction of V 2 O o C 860 mah g 1 at 1A g 1 after 300 cycle 3 Yolk-Shell V 2 O Solvothermal method 180 o C mah g 1 at 0.1A g 1 after 100 cycle 4 Porous V 2 O 3 /C V 2 O 3 -RGO V 2 O 3 /C Nanorods C/VO x microspheres V 2 O 3 /C nanorods Hydrothermal method Reduction of V 2 O 5 Reduction of 200 o C 200 o C 300 mah g 1 at 0.25 A g 1 after 50 cycle 270 mah g 1 at 0.5 A g 1 after 250 cycle V 2 O o C Solvothermal method Reduction of V 2 O o C 210 o C 1100 mah g 1 at 0.1 A g -1 after 100 cycle 183 mah g 1 at 0.1 A g -1 after 100 cycle Estimated value of specific capacity at different discharge current (the calculated potential range from 3.0~0.01 V vs. Li/Li + for GVG electrode). As shown in Table S1, most reported methods are relatively harsh, involving environmentally unfriendly organic solvents. Moreover, most reported methods are relatively harsh, involving environmentally unfriendly organic solvents. Moreover, most reaction temperature is higher than 200 o C, which is unsuitable for mass production. In addition, most reported V 2 O 3 material is large in size, and there is no much control in the structure. Our synthesis method has obvious advantages, and can contributing to excellent lithium storage performance S 1

22 Reference in supporting information [1] L. Zeng, C. Zheng, J. Xi, H. Fei, M. Wei. Carbon, 2013, 62, [2] Y. Dong, R. Mac, M. Hu, H. Cheng, J.-M. Lee, Y. Y. Li, J. A. Zapien. J. Power Sources, 2014, 261, [3] H. Jiang, G. Jia, Y. Hu, Q. Cheng, Y. Fu, C. Li. Ind. Eng. Chem. Res., 2015, 54, [4] L. Jiang, Y. Qu, Z. Ren, P. Yu, L. Wang, H. Fu. ACS Appl. Mater. Interfaces, 2015, 7, [5] Y. Shi, Z. Zhang, D. Wexler, S. Chou, J. Gao, H. D. Abruna, H. Li, H. Liu, Y. Wu, J. Wang. J. Power Sources, 2015, 275, [6] Y. Zhang, A. Pan, S. Liang, T. Chen, Y. Tang, X. Tan. Mater. Lett., 2014, 137, [7] Y. Wang, H. J. Zhang, A. S. Admar. RSC Adv., 2012, 2, [8] C. Niu, M. Huang, P. Wang, J. Meng, X. Liu, X. Wang, K. Zhao, Yang Yu, Y. Wu, C. Lin, L. Mai. Nano Res., 2016, 9, [9] X. Li, J. Fu, Z. Pan, J. Su, J. Xu, B. Gao, X. Peng, L. Wang, X. Zhang, P. K. Chu. J. Power Sources, 2016, 331, S 2