nn9b02129_si_002.avi (8.81 MB)
Dual Bond Enhanced Multidimensional Constructed Composite Silicon Anode for High-Performance Lithium Ion Batteries
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posted on 2019-07-25, 17:34 authored by Shiqi Liu, Xu Zhang, Pengfei Yan, Renfei Cheng, Yushu Tang, Min Cui, Boya Wang, Liqiang Zhang, Xiaohui Wang, Yuyuan Jiang, Lin Wang, Haijun YuThe
development of silicon-based anode materials is important for
improving the energy density of current lithium ion batteries. However,
there are still strong demands for these materials with better cycle
stability and higher reversible capacity. Here, a kind of dual bond
restricted MXene-Si-CNT composite anode materials with enhanced electrochemical
performance is reported. These dual bonds have been clearly revealed
by an X-ray photoelectron spectroscopy technique and also proven by
theoretical calculations with spontaneous reaction energy values (−0.190
and −0.429 eV/atom for Ti–Si and C–Si bonds,
respectively). The cycle stability of the composites, prepared by
a facile ball-milling synthetic method, can obviously be improved
because of the existence of these dual bonds and the multidimensional
constructed architecture. The MXene-Si-CNT composite with 60 wt %
silicon possesses the best overall performance, with ∼80% capacity
retention after 200 cycles, and achieves 841 mAh g–1 at 2 A g–1. This approach demonstrates a promising
strategy to exploit high-performance anode materials and lessens the
immanent negative effect of silicon-based materials. Furthermore,
it is significant to extend this method to other anode materials with
serious volumetric change problems during the cycling process.