Synthesis of C@Si composite materials for lithium battery anode using Chinese rose as carbon source

As a promising anode for lithium-ion batteries (LIBs), silicon (Si) has been studied due to its high specific capacity. However, significant volume change during charge-discharge process has seriously impeded its practical application. Compounding with carbon is one of the methods to solve this problem. In this paper, biomass carbon is prepared by high temperature carbonization of Chinese rose petals. Different mass ratios of Si nanoparticles are embedded in the biomass carbon to produce C@Si composites. The as-prepared C@Si composites are assembled into LIBs to investigate their electrochemical performance. As an anode material for LIBs, the manufactured C@Si composite material (Si-25 wt%) manifests a stable cycling performance (524 mAh•g −1 at 0.1 A•g −1 after 100 cycles), a long cycle life (581 mAh•g −1 at 1 A•g −1 after 400 cycles) and excellent rate capability. And its initial coulombic efficiency at the current density of 1 A•g −1 (99.62 %) is much larger than that of pure nano-Si (29.45 %). The electrochemical impedance spectroscopy (EIS) results indicate that the C@Si composite materials can behave as an ideal capacitor. This study reveals the possibility of changing flower petals to carbon material and the potential applications in the field of LIBs.