A Green and Facile Way to Prepare Granadilla-Like Silicon-Based Anode Materials for Li-Ion Batteries

作者：Zhang, Lei; Rajagopalan, Ranjusha; Guo, Haipeng; Hu, Xianluo; Dou, Shixue^*; Liu, Huakun^*

来源：Advanced Functional Materials, 2016, 26(3): 440-446.

DOI：10.1002/adfm.201503777

• GRAPHITE MICROSPHERES
• CARBON NANOFIBERS
• LITHIUM
• NANOPARTICLES
• PERFORMANCE
• CAPACITY
• STORAGE
• GRAPHENE
• IMPROVEMENT
• COMPOSITES

A yolk-shell-structured carbon@void@silicon (CVS) anode material in which a void space is created between the inside silicon nanoparticle and the outer carbon shell is considered as a promising candidate for Li-ion cells. Untill now, all the previous yolk-shell composites were fabricated through a templating method, wherein the SiO2 layer acts as a sacrificial layer and creates a void by a selective etching method using toxic hydrofluoric acid. However, this method is complex and toxic. Here, a green and facile synthesis of granadilla-like outer carbon coating encapsulated silicon/carbon microspheres which are composed of interconnected carbon framework supported CVS nanobeads is reported. The silicon granadillas are prepared via a modified templating method in which calcium carbonate was selected as a sacrificial layer and acetylene as a carbon precursor. Therefore, the void space inside and among these CVS nanobeads can be formed by removing CaCO3 with diluted hydrochloric acid. As prepared, silicon granadillas having 30% silicon content deliver a reversible capacity of around 1100 mAh g(-1) at a current density of 250 mA g(-1) after 200 cycles. Besides, this composite exhibits an excellent rate performance of about 830 and 700 mAh g(-1) at the current densities of 1000 and 2000 mA g(-1), respectively.

• 出版日期2016-1-20
• 单位华中科技大学