Cluster-derived TiO₂ nanocrystals with multiple carbon coupling for interfacial pseudo-capacitive lithium storage

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Titanium dioxide (TiO2) is a promising anode material for lithium-ion batteries (LIBs) due to its safety and stability.
• Poor electronic and ionic conductivity of TiO2 hinders its practical application in LIBs.

Purpose of the Study:

• To enhance the electrochemical performance of TiO2 as an anode material for LIBs.
• To develop a novel TiO2-based composite with improved conductivity and energy storage capacity.

Main Methods:

• Synthesis of well-defined TiO2 nanocrystals from an atomically precise titanium-oxo cluster (Ti8Ph).
• Coupling of TiO2 nanocrystals with carbon layers and graphene nanosheets to form a TiO2-C-rGO composite.
• Electrochemical testing of the composite as an anode material for LIBs.

Main Results:

• The TiO2-C-rGO composite demonstrated a high capacity of 834 mA h g⁻¹ at 0.1 A g⁻¹ after 300 cycles and 398 mA h g⁻¹ at 5.0 A g⁻¹ after 600 cycles.
• The composite significantly outperformed control samples (TiO2-C, TiO2-rGO, and TiO2) and other reported TiO2 nanostructures.
• Enhanced electron transfer, structural robustness, and pseudo-capacitive lithium storage were observed due to carbon coupling and three-phase interfaces.

Conclusions:

• The rationally designed TiO2-C-rGO composite effectively addresses the conductivity limitations of TiO2 for LIBs.
• This approach offers a new route for fabricating high-efficiency energy materials from molecular clusters.
• The study contributes to the development of advanced anode materials for next-generation LIBs.