Heterostructured TiO₂ Spheres with Tunable Interiors and Shells toward Improved Packing Density and Pseudocapacitive...

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Insertion-type anode materials are crucial for high-performance electrochemical energy storage.
• Developing advanced nanostructures is key to improving ion storage capabilities.

Purpose of the Study:

• To fabricate heterostructured TiO2 spheres with tunable interiors and shells for enhanced sodium-ion storage.
• To investigate the impact of nanosheet integration on packing density and overall performance.
• To elucidate the sodium storage mechanism using density functional theory.

Main Methods:

• Controllable fabrication of heterostructured TiO2 spheres using novel programming methods.
• Integration of nanosheets into the shells of TiO2 spheres.
• Density functional theory (DFT) calculations for sodium intercalation and diffusion analysis.

Main Results:

• Achieved enhanced pseudocapacitive response and favorable Na+ storage kinetics.
• Improved packing density of TiO2 spheres due to integrated nanosheets.
• DFT calculations confirmed a surface-controlled pseudocapacitive Na+ storage mechanism.

Conclusions:

• Heterostructured TiO2 spheres with designed nanostructures offer superior Na+ storage performance.
• The fabrication strategies are effective for developing high-rate and high-volume energy density electrode materials.
• Understanding surface-controlled pseudocapacitive mechanisms is vital for future anode material design.