Nb-Doped TiO₂ with Outstanding Na/Mg-Ion Battery Performance

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Beyond lithium-ion batteries, sodium-ion and magnesium-ion technologies offer abundant resources and high theoretical capacity.
• However, their practical application is hindered by slow reaction kinetics due to large ion sizes and polarity.
• Titanium dioxide (TiO2) is a promising electrode material, but its performance in Na/Mg-ion systems needs improvement.

Purpose of the Study:

• To engineer niobium-doped anatase titanium dioxide (Nb-TiO2) with titanium vacancies.
• To investigate the impact of Nb doping and vacancies on the electrochemical performance of Na/Mg-ion batteries.
• To overcome kinetic limitations in beyond-Li-ion battery systems.

Main Methods:

• Solvothermal synthesis of Nb-doped TiO2.
• Subsequent high-temperature calcination.
• Electrochemical testing of Nb-TiO2 as an electrode material for Na/Mg-ion batteries.

Main Results:

• Nb doping effectively widens diffusion channels for Na+ and Mg2+ ions.
• The presence of cationic vacancies enhances ion storage capacity and electrode conductivity.
• Nb-TiO2 demonstrates significantly improved performance in rechargeable Na/Mg-ion batteries compared to undoped counterparts.

Conclusions:

• Nb-doped anatase TiO2 with Ti vacancies is a viable strategy to enhance beyond-Li-ion battery performance.
• The engineered material addresses kinetic bottlenecks, paving the way for practical Na/Mg-ion battery applications.
• This work contributes to the development of next-generation energy storage solutions.