Supporting Information

Surfactant-templating strategy for ultrathin mesoporous TiO2

coating on flexible graphitized carbon supports for high-

performance lithium-ion battery

Yong Liua, Ahmed A. Elzatahryb, Wei Luoa, c, Kun Lana, Pengfei Zhanga, d, Jianwei Fana,e, Yong Weia,

Chun Wanga, Yonghui Denga, Gengfeng Zhenga, Fan Zhanga, Yun Tanga, Liqiang Maid and Dongyuan

Zhaoa*

a Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, State Key Laboratory of Molecular Engineering of Polymers, Laboratory of Advanced Materials, iChEM (Collaborative Innovation Center of Chemistry for Energy Materials), Fudan University, Shanghai, 200433, China.

b Materials Science and Technology Program, College of Arts and Sciences, Qatar University, P.O. Box 2713, Doha, Qatar

c State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620, P. R. China

d State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology, Hubei, Wuhan 430070 P. R. China

e College of Environmental Science and Engineering, State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, P. R. China.

E-mail: dyzhao@fudan.edu.cn

Homepage: http://www.mesogroup.fudan.edu.cn/

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Figure S1. The TEM image of the intermediate taken from the coating solution after the adding of

TBOT. The TBOT was added dropwise to the dispersion with continuous stirring at room temperature

for 0.5 h. Inset is the mesoscopic structure model of the spherical PEO-PPO-PEO/titania oligomers

composite micelles

The white nanospheres in TEM images represent the PEO-PPO-PEO spherical micelles and the tiny

black dots represent titania oligomers. The TEM images above show that the spherical composite

micelles are initially formed at the interface between the ethanol and DMF phases. The spherical

micelles have a typical core-shell structure with amphiphilic Pluronic triblock copolymer F127 PEO-

PPO-PEO as a core and titania oligomers as a shell.

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Figure S2. TEM images of the multi-wall CNT supports after the pre-treatment with concentrated nitric

acid (68 wt.%). The arrows show that the CNTs have a diameter of ~ 20 nm after nitric acid-pre-

treatment.

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Figure S3. HRTEM images of a single mesoporous CNTs@mTiO2 nanocable. Inset is the structural

model of a single mesoporous CNTs@mTiO2 hybrid nanocable. The dotted red circles represent open

pores exposed on the surface of the CNTs@mTiO2 hybrid nanocable.

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Figure S4. The STEM image (a) and EDX elemental mapping images (b-d) of a single mesoporous

CNTs@mTiO2 hybrid nanocable, white, green, and orange represent oxygen, titanium and carbon

atoms, respectively. Notably, the C element is mainly present in the inner core-shell hybrid nanocable,

confirming that the mesoporous TiO2 shells are coated on the surface of CNTs.

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Figure S5. (a, b) TEM images of the CNTs@TiO2 hybrid nanocables synthesized without F127

templates, showing the nanoparticles-aggregated TiO2 shell structure. (c) HRTEM images recorded on

the surface of a single CNTs@TiO2 hybrid nanocables. Inset (c): the high-magnification TEM of a

cracked CNTs@TiO2 hybrid nanocable, clearly showing the TiO2 nanoparticle shell and a CNT core. (d)

The SAED pattern of a single CNTs@TiO2 hybrid nanocable with a nanoparticles-aggregated shell.

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Figure S6. The TEM image of the mesoporous CNTs@TiO2 hybrid nanocables synthesized with

ammonia concentration of 0.1 vol %, showing that no obvious mesoporous TiO2 shell are formed on the

surface of CNTs.

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Figure S7. The TEM image of the mesoporous CNTs@TiO2 hybrid nanocables synthesized with

ammonia concentration of 0.3 vol %, showing that the thickness of the mesoporous TiO2 shells can

increase to about 60 nm. The thick mesoporous TiO2 shell was easy to be cracked.

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Figure S8. The TEM image of the mesoporous CNTs@TiO2 hybrid nanocables synthesized with

ammonia concentration of 0.4 vol %. As ammonia concentration increases, some large TiO2 spheres

(marked by the dotted line circle) organized from anatase nanoparticles can be observed.

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Figure S9. The SEM image of that flexible CNTs@mTiO2 hybrid mesoporous nanocables after cycling

at 20 C for 500 cycles, showing no notable variation in morphology or collapse after cycling at 20 C for

500 cycles. It should be noted that the small nanoparticles observed in the image are carbon black.

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Figure S10. Cycle performance of the CNTs@TiO2 NPs hybrid nanocables synthesized without

Pluronic F127 templates at a constant current rate of 20 C. Compared to flexible CNTs@mTiO2 hybrid

mesoporous nanocables, the CNTs@TiO2 NPs hybrid nanocables show much lower rate capability of

only about 80 mA h g-1 at a current rate of 20 C due to its low BET surface area (87 m2/g) and pore

volume (0.17 cm3/g).

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1 10 100-100

0

100

200

300

400

Rate (C)

CNT@m TiO2 hybrid nanocables GR@m TiO2 hybrid nanoflakesCNT/TiO2 nanoparticlesCNT/TiO2 mesoporous nanocablesCNT/TiO2 nanocrystals CNT/TiO2 nanosheets

Spec

ific

Cap

acity

(mA

h g

-1)

Figure S11. Comparison of rate-capability of a variety of CNT/TiO2 based high-rate electrodes reported

recently. CNT@mTiO2 hybrid nanocables (our work), CNT@mTiO2 hybrid nanoflakes (our work),

CNT@TiO2 nanoparticles [1], CNT@TiO2 mesoporous nanocables [2], CNT@TiO2 nanocrystals [3] and

CNT@TiO2 nanosheets [4].

References

[1] J. Wang, R. Ran, M.O. Tade, Z. Shao, J. Power. Sources. 254 (2014), 18-28.

[2] L. He, C. Wang, X. Yao, R. Ma, H. Wang, P. Chen, K. Zhang, Carbon, 75 (2014), 345-352.

[3] Z. Chen, D. Zhang, X. Wang, X. Jia, F. Wei, H. Li, Y. Lu, Adv. Mater, 24 (2012), 2030-2036.

[4] S. Ding, J. S. Chen, X. W. Lou, Adv. Funct. Mater. 21 (2011), 4120-4125.

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