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.