Coordination Environment Engineering of Titanium Spinel for Enhanced Lithium Recovery

Area of Science:

• Materials Science
• Chemical Engineering
• Electrochemistry

Background:

• Salt lake brine represents a significant source of lithium carbonate (Li₂CO₃) production, accounting for 35% of global supply.
• Current lithium extraction adsorbents face limitations due to restricted coordination environments, hindering optimal performance.

Purpose of the Study:

• To engineer the coordination environment of titanium spinel (HTO) by controlling exposed crystal facets.
• To enhance lithium ion (Li⁺) adsorption capacity and kinetics through facet engineering.

Main Methods:

• Selective exposure of (110) and (111) crystal facets of HTO.
• Utilizing Density Functional Theory (DFT) calculations.
• Employing Raman spectroscopy and ⁶/⁷Li solid-state NMR (ssNMR) spectroscopy.

Main Results:

• The (111) facet demonstrated a high adsorption capacity of 41.34 mg/g.
• The (110) facet achieved rapid adsorption kinetics, reaching equilibrium in 10 minutes.
• DFT and spectroscopic analyses revealed that tetrahedral Li⁺ sites enhance mobility, while octahedral sites facilitate deeper diffusion and higher capacity.

Conclusions:

• Facet engineering of titanium spinel synergistically improves Li⁺ adsorption performance by modulating coordination environments.
• This approach offers a promising strategy for enhancing ion recovery in lithium extraction.
• The findings provide a foundation for designing next-generation adsorbents for efficient lithium recovery.