Interfacially engineered MXene-MOF hybrid for selective preconcentration of fluoride in salt-rich water samples

MXene-MOF architectural hybrid is prepared for fluoride adsorption. • MSCes exhibit excellent salt tolerance for fluoride adsorption. • MSCes enable efficient fluoride adsorption over a broad pH range. • MSCes perform well in complex environmental samples. Currently, excessive fluoride contamination in groundwater poses a serious threat to drinking water safety, highlighting the need for efficient, simple, and cost-effective strategies for fluoride removal and analysis. Herein, a MXene-engineered Ce-based UiO-66 (MSCe) hybrid is developed for selective fluoride capture and preconcentration from complex water samples. Benefiting from abundant exposed metal sites, reduced interfacial binding resistance, and accelerated mass transfer enabled by MXene engineering, MSCe exhibits excellent structural stability, a broad applicable pH range, high adsorption capacity, and outstanding selectivity toward fluoride. Notably, MSCe maintains excellent fluoride-capture performance even under high-salt conditions, demonstrating its strong tolerance to complex ionic matrices. Among the investigated composites, MSCe-V exhibits the highest adsorption capacity of 218.0 mg g -1 , compared with 194.6 mg g -1 for MSCe-Ti-15, with equilibrium reached within 100 min. The adsorption process followed the pseudo-second-order kinetic and Langmuir isotherm models. This work provides a promising MXene-MOF hybrid platform for selective fluoride preconcentration and expands their application in sample preparation. Download: Download high-res image (176KB) Download: Download full-size image