Nanoconfined materials developed for efficient fluoride removal from water

A research team led by Prof. Kong Lingtao from the Hefei Institutes of Physical Science of the Chinese Academy of Sciences has developed an innovative material for the efficient removal of fluoride ions from water. This newly-developed material, a La-Mg LDH/Ti₃C₂T_X adsorption membrane, utilizes the nano confinement effect to enhance its performance.

The results were published in Chemical Engineering Journal.

Fluoride is a major water pollutant, with high doses causing health risks. Layered double hydroxides (LDHs) are effective at removing fluoride due to their many active sites. However, the typical nanosheet structure makes it prone to material aggregation during preparation, which affects the exposure of active sites and results 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, the researchers developed a new material called La-Mg LDH/Ti₃C₂T_X to remove fluoride ions from water. They designed this material by combining La-Mg LDH with Ti₃C₂T_X, 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/Ti₃C₂T_X material can absorb fluoride 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. In addition, the levels of magnesium, titanium, and lanthanum in the filtered water remain below national safety standards, demonstrating 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 Ti₃C₂T_X, rather than just on the surface. The material has a high water flow rate, indicating that it has great potential for practical use in water treatment.

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

“Our study could lead to more effective methods for water purification,” said Dr. He Junyong.