A hierarchical porous architecture of silicon@TiO2@carbon composite novel anode materials for high performance Li-ion batteries

Abstract

Silicon (Si) is a promising candidate as an ideal anode material for lithium-ion batteries (LIBs). However, owing to the large volume change during charging and discharging, the cycle life and coulombic efficiency is significantly reduced, which limits its commercial application. Herein, a hierarchical porous architecture of Si@titanium dioxide@carbon (Si@TiO₂@C) composite was designed and fabricated by solvothermal and carbon encapsulation processes. The composite exhibits an excellent electrochemical performance of about 983.4 and 531.5 mA h g⁻¹ after 100 cycles at 0.1 and 2.0 A g⁻¹, respectively. The hierarchical porous TiO₂ plays an effective role in buffering Si expansion during charging and discharging. The typical structure and high surface area are conducive to rapid Li⁺ diffusion into the electrode, thus improving the electrochemical properties. The carbon shell on the SNP surface is connected to the TiO₂ anchoring and coating SNPs. At the same time, the carbon shell encapsulating the SiNPs can improve the electrode conductivity.