Titanosilicate Derived SiO₂/TiO₂@C Nanosheets with Highly Distributed TiO₂ Nanoparticles in SiO₂ Matrix as Robust Lithium Ion Battery Anode

Carbon-coated SiO 2 /TiO 2 (SiO 2 /TiO 2 @C) nanosheets consisting of TiO 2 nanoparticles uniformly embedded in SiO 2 matrix and a carbon-coating layer are fabricated by using acidified titanosilicate JDF-L1 nanosheets as template and precursor. SiO 2 /TiO 2 @C has unique structural features of sheetlike nanostructure, ultrafine TiO 2 nanoparticles distributed in SiO 2 matrix, and carbon coating, which can expedite ion diffusion and electron transfer and relieve volume expansion efficiently, and thus, the synergetic combination of these advantages significantly enhances its Li storage capability. As anode of lithium-ion batteries (LIBs), SiO 2 /TiO 2 @C nanosheets exhibit a high capacity of 998 mAh g –1 at 100 mA g –1 after 100 cycles. Moreover, an ultrahigh capacity of 410 mAh g –1 retains at 2000 mA g –1 after 400 cycles. A mixed reaction mechanism of capacitance and diffusion-controlled intercalation is revealed by qualitative and quantitative analysis.