Three-dimensional carbon-coating silicon nanoparticles welded on carbon nanotubes composites for high-stability lithium-ion battery anodes

Abstract

Although silicon (Si) is regarded as one of promising anode materials in next-generation lithium-ion batteries (LIBs) due to the high specific capacity, commercial application is stifled by the large volume effect and small electric conductivity. Using rice husk (RH) biomass as nano Si source (RH-Nano Si), here we designed and fabricated the three-dimensional (3D) carbon-hybridized nano-Si hierarchical architecture composite (RH-Nano Si@C/CNT) via assembling Si with CNT by the self-electrostatic route, reinforcing by hydrothermal treating in a glucose solution, and calcination in Ar. In RH-Nano Si@C/CNT, the Si nanoparticles are anchored on the 3D conductive CNT network by the glucose-derived carbon through welding and coating, thus providing enhanced electrical contact and high structural integrity. As anode materials, RH-Nano Si@C/CNT exhibits improved rate capability and prolonged cycling stability compared to Si and CNT self-electrostatic sample. Boasting a high reversible capacity of 989.5 mAh g−1 at 0.5C (1C = 4.2 A g−1) and 345 mAh g−1 at 3C as well as low capacity decay of 0.035% per cycles after 1000 cycles, RH-Nano Si@C/CNT produced by this technique is promising as anodes in LIBs.