Inserting Sn Nanoparticles into the Pores of TiO2−x–C Nanofibers by Lithiation |
| |
Authors: | Xiaoyan Li Yuming Chen Hongtao Wang Haimin Yao Haitao Huang Yiu‐Wing Mai Ning Hu Limin Zhou |
| |
Affiliation: | 1. Department of Mechanical Engineering, The Hong Kong Polytechnic University, Hong Kong, China;2. Institute of Applied Mechanics, Zhejiang University, Hangzhou, China;3. Department of Applied Physics and Materials Research Center, The Hong Kong Polytechnic University, Hong Kong, China;4. Centre for Advanced Materials Technology (CAMT), School of Aerospace, Mechanical and Mechatronics Engineering J07, The University of Sydney, NSW, Australia;5. College of Aerospace Engineering, Chongqing University, Chongqing, China |
| |
Abstract: | Tin holds promise as an anode material for lithium‐ion batteries (LIBs) because of its high theoretical capacity, but its cycle life is limited by structural degradation. Herein, a novel approach is exploited to insert Sn nanoparticles into the pores of highly stable titanium dioxide–carbon (TiO2?x–C) nanofiber substrates that can effectively localize the postformed smaller Sn nanoparticles, thereby address the problem of structural degradation, and thus achieve improved anode performance. During first lithiation, a Li4.4Sn alloy is inserted into the pores surrounding the initial Sn nanoparticles in TiO2?x–C nanofibers by its large volume expansion. Thereafter, the original Sn nanoparticle with a diameter of about 150 nm cannot be recovered by the delithiation because of the surface absorption between inserted Sn nanoparticles and the TiO2?x–C substrate, resulting in many smaller Sn nanoparticles remaining in the pores. Batteries containing these porous TiO2?x–C–Sn nanofibers exhibit a high capacity of 957 mAh g?1 after 200 cycles at 0.1 A g?1 and can cycle over 10 000 times at 3 A g?1 while retaining 82.3% of their capacity, which represents the longest cycling life of Sn‐based anodes for LIBs so far. This interesting method can provide new avenues for other high‐capacity anode material systems that suffer from significant volume expansion. |
| |
Keywords: | electrospinning in situ TEM lithiation‐induced insertion lithium‐ion batteries TiO2− x– C– Sn hybrid nanofibers |
|
|