Nanoconfined materials developed for efficient fluoride removal from water

Recently, the research team led by Prof. KONG Lingtao at Institute of Solid State Physics, the Hefei Institutes of Physical Science of the Chinese Academy of Sciences developed an innovative material for the efficient removal of fluoride ions from water. This newly developed material, a La-Mg LDH/Ti₃C₂TX adsorption membrane, leverages the nano confinement effect to enhance its performance.

The results are published in Chemical Engineering Journal.

Fluoride is a major water pollutant, with high doses causing health risks. Layered double hydroxides (LDH) are effective for removing fluoride due to their many active sites. However, the typical nanosheet structure makes it prone to material aggregation during preparation, impacting the exposure of active sites and resulting in a significant decrease in adsorption capacity. Therefore, it's important to design LDH materials that fully expose their active sites to efficiently remove fluoride ions.

In this study, researchers developed a new material called La-Mg LDH/Ti₃C₂TX to remove fluoride ions from water. They designed this material by combining La-Mg LDH with Ti₃C₂TX, which helps prevent the La-Mg LDH sheets from clumping together. This combination increases the surface area and active sites of the material, making it more effective at capturing fluoride ions.

The La-Mg LDH/Ti₃C₂TX material can absorb fluoride per gram, and other common ions in the water. Even after being used and regenerated five times, the material still removes over 80% of the fluoride ions from water. Additionally, the levels of magnesium, titanium, and lanthanum in the filtered water remain below national safety standards, showing that the material is stable and safe.

Computer simulations confirmed that fluoride ions are more easily trapped at the interface between La-Mg LDH and Ti₃C₂TX rather than just on the surface. The material has a high water flow rate, indicating it has great potential for practical use in water treatment.

This research presents a new solution to improve the adsorption capacity of materials used for fluoride removal by addressing the issue of material aggregation.

"Our study could lead to more effective methods for purifying water," said Dr. HE Junyong, a member of the team.

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