Thermal Burst Synthesis of High-Performance Si Nanotube Sheets for Lithium-Ion Batteries

One of the drawbacks of Si-based battery anodes is poor cycle stability due to volume expansion of the anode material. To overcome this limitation, we propose a novel strategy of Si nanotube sheet synthesis using the thermal burst method. Herein, SiO2 nanotubes are prepared using the hard template method; subsequently, Si nanotube sheets are produced during the thermal burst caused by magnesiothermic reduction, which occurs because nanotubes are broken by ZnO with a larger thermal expansion coefficient. The electrochemical test results indicate that the Si nanotube sheets possess excellent electrochemical properties. The discharge specific capacity can reach 712.7 mAh g(-1) even at the current density of 5 A g(-1). Moreover, after carbon coating, a discharge capacity of 695.9 mAh g(-1) is retained after 400 cycles at 1 A g(-1) and the capacity retention of full batteries can reach 81.78% after 50 cycles at a rate of 0.5 C. Thus, the Si-based anode electrode with excellent electrochemical performance can be prepared by the thermal burst process, and this strategy can be applied to the preparation of other anode materials.