Screening Precursor-Solvent Combinations for Li₄Ti₅O₁₂ Energy Storage Material Using Flame Spray Pyrolysis

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Advanced lithium-based energy storage materials require innovative production techniques and cost-effective precursors.
• Flame spray pyrolysis (FSP) offers a promising solution for scalable, controlled, and versatile synthesis of these materials.

Purpose of the Study:

• To design phase-pure lithium titanate (Li4Ti5O12) anode material using FSP.
• To systematically screen lithium and titanium precursors and organic solvents for optimal nanoparticle synthesis.
• To investigate the influence of precursor and solvent properties on particle formation mechanisms.

Main Methods:

• Flame spray pyrolysis (FSP) for Li4Ti5O12 nanoparticle synthesis.
• Systematic screening of lithium and titanium precursors in five organic solvents.
• Characterization using X-ray diffraction (Rietveld refinement), TGA-DSC-MS, gas adsorption, vibrational spectroscopy, and HR-TEM.

Main Results:

• Presence of carboxylic acid in precursor solutions yielded pure (>95%) and homogeneous Li4Ti5O12 nanoparticles (4-9 nm).
• Carboxylic acid stabilized water-sensitive precursors and facilitated volatile carboxylate formation.
• Absence of carboxylic acid led to inhomogeneous TiO2 particles with significantly reduced Li4Ti5O12 content (∼34%).

Conclusions:

• FSP is a viable and inexpensive gas-phase synthesis method for high-quality energy storage materials.
• Optimized precursor and solvent selection is crucial for controlling nanoparticle purity, size, and morphology.
• Synthesized Li4Ti5O12 nanoparticles exhibit excellent rate capability and charge reversibility, demonstrating significant potential for energy storage applications.