Synthesize of silicon/carbon nanosheets with NaCl template and its application as anode material of lithium-ion batteries

Lithium-ion batteries (LIBs) are used extensively in various applications such as mobile phones and portable computer. Silicon (Si) is regarded as a kind of promising anode material in LIBs because of its high theoretical capacity and low working potential. The major challenges related to Si anodes are their huge volume changes and poor conductivity during lithiation–delithiation. Herein, a two-dimensional structure of Si/petroleum pitches based carbon nanosheets (Si/CNSs) was successfully synthesized via a green and recyclable NaCl template method. This peculiar structural feature of Si/CNS can effectively accommodate the volume expansion of Si anodes and improve their electrochemical performance. A typical sample of Si/CNS-2 exhibits a high reversible capacities of 901 mAh g− 1 at 100 mA g− 1, good cycling stability (capacity retention of 655 mAh g− 1 after 100 cycles at 300 mA g− 1) and excellent rate capability (533 mAh g− 1 at 2 A g− 1). This approach is simple and environment-friendly, which may supply a practicality way to prepare Si-based anode materials for high-performance LIBs.