Supporting Information for Metal Organic Framework-Derived Metal Oxide Embedded in Nitrogen-Doped Graphene Network for High-Performance Lithium-Ion Batteries Zhu-Yin Sui, Pei-Ying Zhang,, Meng-Ying Xu, Yu-Wen Liu, Zhi-Xiang Wei,*,, and Bao-Hang Han*,, CAS Key Laboratory of Nanosystem and Hierarchical Fabrication, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China Department of Environment and Chemical Engineering, Yanshan University, Qinhuangdao 066004, China University of Chinese Academy of Sciences, Beijing 100049, China Tel: +86 10 8254 5576. E-mail: hanbh@nanoctr.cn. Tel: +86 10 8254 5565. E-mail: weizx@nanoctr.cn. S 1
Experimental Section Preparation of NGA NGA was obtained from a hydrothermal process as our previous work reported. S1 In a typical procedure, the mixture of aqueous graphene oxide dispersion (18 ml, 5 mg ml 1 ) and ammonia solution (4 ml, 28 wt %) was sealed in a Teflon-lined autoclave and heated at 180 C for 12 h, thus producing a black nitrogen-doped graphene hydrogel. After that, nitrogen-doped graphene hydrogel was dialyzed for 3 days to remove the impurities and freeze-dried for 24 h under vacuum to obtain the product, NGA. S 2
Figure S1. The digital pictures of NGA, which was immersed into water, methanol, and N,N-dimethylformamide (DMF), respectively. S 3
Figure S2. SEM images (a and b) of NGA treated in a hydrothermal condition (at 120 C for 24 h in water); SEM images (c and d) of NGA treated in a solvothermal condition (at 120 C for 24 h in DMF). S 4
Figure S3. SEM images of ZIF-8@NGA (a and b) and UiO-66@NGA (c and d) at different magnifications. S 5
Intensity / a.u. NGA ZIF-67@NGA ZIF-67 10 20 30 40 50 2 theta / degree Intensity / a.u. NGA ZIF-8@NGA ZIF-8 10 20 30 40 50 2 theta / degree Intensity / a.u. NGA UiO-66@NGA UiO-66 10 20 30 40 50 2 theta / degree Figure S4. XRD patterns of NGA, pristine MOFs (ZIF-67, ZIF-8, and UiO-66), and MOF-containing NGA (ZIF-67@NGA, ZIF-8@NGA, and UiO-66@NGA). S 6
100 Mass Remaining / % 80 60 Co 3 O 4 @NGN 40 ZIF-67 20 ZIF-67@NGA NGA 0 0 200 400 600 800 Temperature / o C Figure S5. TGA curves of NGA, ZIF-67, ZIF-67@NGA, and Co 3 O 4 @NGN in air. The mass remaining of NGA, ZIF-67, and ZIF-67@NGA is 0, 38.7, and 13.3 wt %, respectively. It can be concluded that the mass ratio of NGA and ZIF-67 in the ZIF-67@NGA composite is ~2:1. In addition, the weight percentage of NGN in the Co 3 O 4 @NGN composite is estimated to be ~56.6 wt %. S 7
Figure S6. SEM images of ZIF-67 (a), ZIF-67 derived Co 3 O 4 (b), NGA (c) and NGN (d). S 8
Figure S7. TEM images of Co 3 O 4 @NGN at low (a) and high (b) magnifications (Inset is the high-resolution TEM image of Co 3 O 4. S 9
Adsorbed Volume / cm 3 (STP) g -1 1200 1000 800 600 400 a ZIF-67@NGA 200 Co 3 O 4 0 0.0 0.2 0.4 0.6 0.8 1.0 Relative Pressure (P/P 0 ) Pore Volume, dv/dd (cm 3 g -1 nm -1 ) 0.015 0.012 0.009 0.006 0.003 b 0.000 1 10 100 Pore Width (nm) Figure S8. (a) Nitrogen adsorption desorption isotherm at 77 K of ZIF-67@NGA and Co 3 O 4 ; (b) Barret Joyner Halenda desorption PSD profile of Co 3 O 4 @NGN composite. S 10
N 1s Intensity / a.u. Pyridinic N Pyrrolic N Quaternary N 396 398 400 402 404 406 Binding Energy / ev Figure S9. N 1s spectrum of Co 3 O 4 @NGN composite. S 11
2000 Capacity / ma h g -1 1600 1200 800 400 100 200 400 600 1000 100 0 10 20 30 40 50 60 Cycle Number Figure S10. Rate capability of Co 3 O 4 /NGN composite at various charge/discharge rates (100, 200, 400, 600, and 1000 ma g 1 ). S 12
Capacity / ma h g -1 1600 1400 1200 1000 800 600 400 200 0 200 ma g -1 Co 3 O 4 /NGA 20 40 60 80 100 Cycle Number Figure S11. Cycling stability of Co 3 O 4 /NGA at 200 ma g 1. S 13
-Z'' / Ohm 350 300 250 200 150 100 50 Co 3 O 4 @NGN Co 3 O 4 NGN 0 0 50 100 150 200 250 300 350 400 450 500 Z' / Ohm Figure S12. Nyquist plots of Co 3 O 4 @NGN composite, NGN, and Co 3 O 4 electrodes. S 14
Table S1. Electrochemical performance comparison of the Co 3 O 4 @NGN electrode with graphene or MOF-derived materials for LIBs. Electrode Current (ma g 1 ) Capacity retention (Capacity in mah g 1 ) Cycle number Ref. Co 3 O 4 @NGN 200 955 100 This work Co 3 O 4 @NGN 1000 676 400 This work NPGM a 400 496 200 [S2] NGS b 100 727 100 [S3] graphene nanosheets 1000 557 300 [S4] MWCNTs/Co 3 O 4 100 813 100 [S5] MWCNTs/ZnCo 2 O 4 100 755 100 [S5] NiFe 2 O 4 /Fe 2 O 3 nanotubes 100 937 100 [S6] hollow Zn x Co 3 x O 4 100 990 50 [S7] Fe 2 O 3 @NiCo 2 O 4 nanocages 200 904 100 [S8] hierarchical Fe 2 O 3 microboxes 200 945 30 [S9] Co 3 O 4 /ZnO hybrids 1000 ~550 1000 [S10] porous Co 3 O 4 /N C c 1000 612 500 [S11] a nitrogen-doped porous graphene; b nitrogen-doped graphene sheet; c porous nitrogen-doped carbon coated Co 3 O 4 fish-scale structures. References [S1] Sui, Z.-Y.; Meng, Y.-N.; Xiao, P.-W.; Zhao, Z.-Q.; Wei, Z.-X.; Han, B.-H. Nitrogen-Doped Graphene Aerogels as Efficient Supercapacitor Electrodes and Gas Adsorbents. ACS Appl. Mater. Interfaces 2015, 7 (3), 1431 1438. [S2] Sui, Z.-Y.; Wang, C.; Yang, Q.-S.; Shu, K.; Liu, Y.-W.; Han, B.-H.; Wallace, G. A S 15
Highly Nitrogen-Doped Porous Graphene An Anode Material for Lithium Ion Batteries. J. Mater. Chem. A 2015, 3 (35), 18229 18237. [S3] Tian, L.; Wei, X.; Zhuang, Q.; Jiang, C.; Wu, C.; Ma, G.; Zhao, X.; Zong, Z.; Sun, S. Bottom-Up Synthesis of Nitrogen-Doped Graphene Sheets for Ultrafast Lithium Storage. Nanoscale 2014, 6 (11), 6075 6083. [S4] Cai, D.; Wang, S.; Ding, L.; Lian, P.; Zhang, S.; Peng, F.; Wang, H. Superior Cycle Stability of Graphene Nanosheets Prepared by Freeze-Drying Process as Anodes for Lithium-Ion Batteries. J. Power Sources 2014, 254, 198 203. [S5] Huang, G.; Zhang, F.; Du, X.; Qin, Y.; Yin, D.; Wang, L. Metal Organic Frameworks Route to in Situ Insertion of Multiwalled Carbon Nanotubes in Co 3 O 4 Polyhedra as Anode Materials for Lithium-Ion Batteries. ACS Nano 2015, 9 (2), 1592 1599. [S6] Huang, G.; Zhang, F. F.; Zhang, L. L.; Du, X. C.; Wang, J. W.; Wang, L. M. Hierarchical NiFe 2 O 4 /Fe 2 O 3 Nanotubes Derived from Metal Organic Frameworks for Superior Lithium Ion Battery Anodes. J. Mater. Chem. A 2014, 2 (21), 8048 8053. [S7] Wu, R. B.; Qian, X. K.; Zhou, K.; Wei, J.; Lou, J.; Ajayan, P. M. Porous Spinel Zn x Co 3 x O 4 Hollow Polyhedra Templated for High-Rate Lithium-Ion Batteries. ACS Nano 2014, 8 (6), 6297 6303. [S8] Huang, G.; Zhang, L. L.; Zhang, F. F.; Wang, L. M. Metal Organic Framework Derived Fe 2 O 3 @NiCo 2 O 4 Porous Nanocages as Anode Materials for Li-Ion Batteries. Nanoscale 2014, 6 (10), 5509 5515. [S9] Zhang, L.; Wu, H. B.; Madhavi, S.; Hng, H. G.; Lou, X. W. Formation of Fe 2 O 3 Microboxes with Hierarchical Shell Structures from Metal Organic Frameworks and S 16
Their Lithium Storage Properties. J. Am. Chem. Soc. 2012, 134 (42), 17388 17391. [S10] Fang, G. Z.; Zhou, J.; Cai, Y. S.; Liu, S. N.; Tan, X. P.; Pan, A. Q.; Liang, S. Q. Metal Organic Framework-Templated Two-Dimensional Hybrid Bimetallic Metal Oxides with Enhanced Lithium/Sodium Storage Capability. J. Mater. Chem. A 2017, 5 (27), 13983 13993. [S11] Han, X.; Chen, W. M.; Han, X. G.; Tan, Y. Z.; Sun, D. Nitrogen-Rich MOF Derived Porous Co 3 O 4 /N C Composites with Superior Performance in Lithium-Ion Batteries. J. Mater. Chem. A 2016, 4 (34), 13040 13045. S 17