Titanosilicate Derived SiO₂/TiO₂@C Nanosheets with Highly Distributed TiO₂ Nanoparticles in SiO₂ Matrix as Robust...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Developing high-performance anode materials is crucial for advancing lithium-ion batteries (LIBs).
• Silicon dioxide (SiO2) and titanium dioxide (TiO2) are promising but face challenges like volume expansion and low conductivity.
• Nanostructured materials offer unique advantages for energy storage applications.

Purpose of the Study:

• To fabricate and characterize carbon-coated SiO2/TiO2 nanosheets (SiO2/TiO2@C) as an anode material for LIBs.
• To investigate the structural features and electrochemical performance of the synthesized material.
• To understand the lithium storage mechanism in the SiO2/TiO2@C nanosheets.

Main Methods:

• Fabrication of SiO2/TiO2@C nanosheets using acidified titanosilicate JDF-L1 nanosheets as a template and precursor.
• Characterization of the material's structure, including nanoparticle distribution and carbon coating.
• Electrochemical testing of the SiO2/TiO2@C nanosheets as an anode in LIBs, including cycling stability and rate capability tests.
• Analysis of the lithium storage mechanism using qualitative and quantitative methods.

Main Results:

• SiO2/TiO2@C nanosheets possess a unique sheetlike nanostructure with ultrafine TiO2 nanoparticles embedded in an SiO2 matrix and a carbon coating.
• The material exhibits excellent lithium storage capability, with a high capacity of 998 mAh g-1 at 100 mA g-1 after 100 cycles.
• Remarkable capacity retention of 410 mAh g-1 at 2000 mA g-1 after 400 cycles was achieved.
• A mixed reaction mechanism involving capacitance and diffusion-controlled intercalation was identified.

Conclusions:

• The synergetic combination of nanostructure, ultrafine TiO2 dispersion, and carbon coating in SiO2/TiO2@C nanosheets significantly enhances lithium storage performance.
• The developed material demonstrates high capacity, excellent rate capability, and long-term cycling stability, making it a promising anode for next-generation LIBs.
• Understanding the mixed reaction mechanism provides insights for further optimization of anode materials for LIBs.