In this work, silicon@reduced graphene oxide/pyrolytic carbon nanofibers (Si@RGO/C NFs) composite with double modified layer is prepared through electrospinning, stabilization and carbonization. In this composite, polyethylene oxide–polypropylene oxide–polyethylene oxide (P123, a non-ionic surfactant) is introduced as the dispersant, which can make silicon nanoparticles evenly dispersed in electrospinning solution to prevent it from agglomeration. Graphene modified layer can buffer the volumetric expansion of silicon nanoparticles, prevent direct contact between silicon and electrolyte as well as enhance the electrical conductivity. Moreover, carbon fibers synthesized by electrospinning can encapsulate silicon@graphene composite internally to form a double modified layer. This composite with double modified layer can further alleviate the volume change of silicon nanoparticles and avoid direct contact between silicon and electrolyte to form a stable interface. Owing to the above-mentioned merits, the Si@RGO/C NFs composite exhibits excellent cyclic stability and superior rate performance. Particularly, it maintains a specific capacity of 929 mA h g⁻¹ with the retention ratio of 83.1% after 100 cycles at 0.5 A g⁻¹ and delivers an outstanding rate capability of 1003 mA h g⁻¹ at 2 A g⁻¹.

本文通过静电纺丝，稳定化和碳化制备了具有双层改性层的硅还原氧化石墨烯/热解碳纳米纤维（Si @ RGO / C NFs）复合材料。在这种复合材料中，引入了聚环氧乙烷-聚环氧丙烷-聚环氧乙烷（P123，一种非离子表面活性剂）作为分散剂，可以使硅纳米颗粒均匀地分散在静电纺丝溶液中以防止其团聚。石墨烯改性层可以缓冲硅纳米颗粒的体积膨胀，防止硅与电解质直接接触，并增强导电性。而且，通过静电纺丝合成的碳纤维可以在内部包封硅石墨烯复合物以形成双改性层。具有双重改性层的这种复合材料可以进一步减轻硅纳米颗粒的体积变化，并且避免硅与电解质之间直接接触以形成稳定的界面。由于上述优点，Si @ RGO / C NFs复合材料表现出优异的循环稳定性和优异的速率性能。特别是，它保持了929 mA h g的比容量^-1在0.5 A g ^-1下经过100次循环后的保留率为83.1％，并在2 A g ^-1下具有1003 mA h g ^-1的出色速率能力。