The reusability and practical feasibility of La-fum, Zr-fum, and Ce-fum MOFs were rigorously tested through multiple regeneration cycles. After adsorption of arsenate and fluoride from binary solutions, the materials were eluted using 0.01 M HNO₃, effectively desorbing contaminants without significant structural degradation. The regenerated MOFs maintained high adsorption capacity over six consecutive cycles for both ions, demonstrating excellent stability and reversibility. ICP-OES analysis confirmed minimal residual arsenate and fluoride levels after each cycle, indicating efficient regeneration and low leaching risk. Notably, La-fum and Ce-fum retained >90% of their initial capacity even after repeated use, while Zr-fum showed slightly reduced performance due to its amorphous nature and partial dissolution during acid treatment. These results affirm the long-term viability of the materials for continuous water purification processes. Furthermore, the absence of post-synthetic modifications or complex functionalization simplifies scalability and reduces production costs. The ability to operate under real-world conditions—such as varying pH, coexisting anions, and multi-cycle use—positions these defective MOFs as promising candidates for industrial wastewater treatment, especially in regions affected by arsenic and fluoride contamination. Their compatibility with existing water infrastructure and ease of integration underscore their potential for large-scale deployment.
Defect Engineering and Structural Advantages in Metal-Organic Frameworks
Defect engineering plays a pivotal role in enhancing the functionality of metal-organic frameworks (MOFs), particularly in environmental applications. In this study, the controlled introduction of defects into the UiO-66 architecture via modulator-free synthesis significantly improved the adsorption performance of La-fum, Zr-fum, and Ce-fum MOFs.STAT5a Antibody MedChemExpress The average number of defects per cluster was calculated at 3.8 for La-fum, 4.6 for Zr-fum, and 4.2 for Ce-fum—substantially higher than the pristine UiO-66 structure. These defects create additional active sites and enhance surface accessibility, facilitating stronger interactions with arsenate and fluoride ions. Despite Zr-fum’s amorphous character and incomplete crystallization, its defect-rich structure enabled superior contaminant uptake compared to many fully crystalline analogues. This phenomenon highlights that structural imperfections are not inherently detrimental; rather, they can be strategically exploited to boost functionality. The presence of unsaturated metal sites and open coordination environments increases binding affinity, particularly for anions with high charge density. Moreover, the defect-induced porosity enhances mass transfer and diffusion kinetics, contributing to faster adsorption rates. This work advances the paradigm that intentional defect creation is a powerful tool in MOF design, enabling tailored materials with enhanced selectivity, capacity, and stability for targeted environmental remediation tasks.
Comparative Performance of Lanthanide-Based MOFs in Toxic Ion Capture
Among the three synthesized MOFs, lanthanide-based materials—La-fum and Ce-fum—demonstrated markedly superior performance in capturing arsenate and fluoride compared to their zirconium counterpart.FITC-conjugated Goat Anti-Human IgG Fc Data Sheet This superiority stems from the unique electronic and coordination properties of lanthanide ions, which exhibit strong affinities for oxyanions due to their high charge density and flexible coordination geometry.PMID:34872086 La³⁺ and Ce³⁺ ions form stable monodentate complexes with arsenate and fluoride, as confirmed by EXAFS and XPS data. The higher basicity of La³⁺ compared to Ce³⁺ allows it to bind more strongly with negatively charged pollutants, resulting in greater adsorption densities in both single and binary systems. While Ce-fum showed slightly lower capacities, it still outperformed most reported materials in the literature. In contrast, Zr-fum, despite having a similar framework type, exhibited inferior performance due to incomplete crystallization and lack of modulator support, leading to reduced surface area and fewer accessible active sites. Nevertheless, its defect-rich nature partially compensated for structural limitations, proving that even non-ideal MOFs can serve as effective adsorbents when defect engineering is optimized. These findings emphasize the critical role of metal cation selection in MOF design and validate lanthanide-based frameworks as highly effective platforms for simultaneous removal of toxic anions from contaminated water sources.MedChemExpress (MCE) offers a wide range of high-quality research chemicals and biochemicals (novel life-science reagents, reference compounds and natural compounds) for scientific use. We have professionally experienced and friendly staff to meet your needs. We are a competent and trustworthy partner for your research and scientific projects.Related websites: https://www.medchemexpress.com