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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. [ABSTRACT FROM AUTHOR]

On page 440, S. Dou, H. Liu, and co‐workers present yolk‐shell‐structured carbon@void@silicon (CVS) anode material as a promising candidate for Li‐ion cells. The anode material is composed of an interior carbon network supporting the CVS yolk–shell silicon nanobeads. Fabrication of the anode material is achieved via a simple and green templating method. [ABSTRACT FROM AUTHOR]