Facile kinetics of Li-ion intake causes superior rate capability in multiwalled carbon nanotube@TiO2 nanocomposite battery anodes

JOURNAL OF POWER SOURCES

卷:268

Article

Acevedo-Pena, Prospero¹  Haro, Marta²  Rincon, Marina E.¹  Bisquert, Juan²  Garcia-Belmonte, Germa² 

[1] Univ Nacl Autonoma Mexico, Inst Energias Renovables, Temixco 62580, Mexico

[2] Univ Jaume 1, Dept Fis, Photovolta & Optoelect Devices Grp, Castellon de La Plana 12071, Spain

关键词: Li-ion batteries;    Core-shell materials;    Carbon nanotubes;    TiO2;    Electrode kinetics;    Electrochemical impedance spectroscopy;   

DOI  :  10.1016/j.jpowsour.2014.06.058

来源: Elsevier

【 摘 要 】

Nanotechnology produces hybrids with superior properties than its individual constituents. Here MWCNT@TiO2 composites have been synthesized by controlled hydrolysis of titanium isopropoxide over MWCNT, to be incorporated into Li-ion battery electrodes. Outstanding rate capability of the coated nanotubes is observed in comparison to pristine TiO2. Specific storage capacity as high as 250 mAh g(-1) is achieved for the nanocomposite electrode which doubles that encountered for TiO2-based anodes. The mechanism explaining the enhancement in power performance has been revealed by means of electrochemical impedance methods. Although both pristine TiO2 and MWCNT@TiO2 would potentially exhibit comparable specific capacity, the charge transfer resistance for the latter is reduced by a factor 10, implying a key role of MWCNTs to favor the interfacial Li+ ion intake from the electrolyte. MWCNT efficiently provides electrons to the nanostructure through the Ti-C bond which assists the Li+ ion incorporation. These findings provide access to the detailed lithiation kinetics of a broad class of nanocomposites for battery applications. (C) 2014 Elsevier B.V. All rights reserved.

【 授权许可】

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