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Metal–organic frameworks (MOFs) stand out as remarkable materials renowned for their exceptionally high surface area and large number of pores, making them invaluable for diverse sensing applications including gas, biomedical, chemical, and optical sensing. Traditional methods of molecule infusion and release often involve a large number of crystals with varying shapes and sizes, leading to averaged outcomes across a heterogeneous crystal population. In this study, we present continuous monitoring of the infusion and release dynamics of model drug molecules, specifically vitamin B12, within individual Tb-mesoMOF crystals. Our findings underscore the critical influence of crystal size and shape on the infusion and diffusion processes and corresponding color change, underscoring the necessity to account for these factors in the design of large-scale systems. Leveraging optical microscopy, we employed a histogram-based algorithm for image processing, enabling automated tracking of diffusion phenomena. This investigation offers crucial insights into the dynamics of these processes, laying the groundwork for optimizing parameters in future sensing systems. [ABSTRACT FROM AUTHOR]

Per- and polyfluoroalkyl substances (PFAS) are man-made environmental contaminants causing increasing global concern due to their adverse effect on environmental and human health. Conventional treatment methods are ineffective in removing short-chain PFAS because they are persistent and recalcitrant to treatment. This study evaluated the performance of a structurally-tunable and chemically-stable porous organic polymer (POP) for PFAS removal under realistic environmental conditions. The POP demonstrated an exceptionally high removal efficiency (>95%) within 15 min when the initial PFAS concentration was approximately 400 ng/L. The adsorption of PFAS on the POP was not significantly affected by changes in solution pH within the range of 5–9. The common co-contaminants in water competed with short-chain PFAS for active sites during the adsorption process following the order of natural organic matter (NOM), long-chain PFAS, and Cl−. The Freundlich-type model could predict the multicomponent interactions well with a R2 value above 0.91. The spent POP was effectively regenerated using a mixture of the 10% NaCl and 30% methanol solution and the PFAS removal maintained at 90% through five adsorption and desorption cycles. The characteristics of the designed POP make it a highly promising and stable absorbent. It enables fast and effective removal of short-chain PFAS. [Display omitted] • Cationic POP shows a fast adsorption rate and a high capacity for PFAS removal. • The designed POP maintained above 85% removal for PFBA at a pH range of 5–9. • The effect of the co-contaminants on PFBA removal followed the order of HA > PFOS > Cl−. • PFAS removal maintained at 90% in five consecutive adsorption/regeneration cycles. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel Zr(IV)-based MOF with high-density free carboxylic groups was constructed. • The MOF demonstrates high stability and excellent uranium removal performance. • Dynamic sorption tests highlight its potential for treating radioactive wastewater. • The mechanism for its excellent ability to adsorb U(VI) was investigated. The extraction of uranium from aqueous environments, including the ocean and radioactive wastewater, represents a significant challenge with profound implications for energy resources and environmental remediation. This work presents the design and synthesis of a novel highly stable carboxylated metal–organic framework, BUT-12-3COOH, which achieves excellent U(VI) extraction ability from water. BUT-12-3COOH features high-density free carboxylic groups, exceptional chemical stability, fast kinetics, and high adsorption capacity for U(VI). Dynamic sorption experiments further demonstrated the potential of BUT-12-3COOH in treating real radioactive wastewater. The mechanisms for the U(VI) capture of BUT-12-3COOH are investigated through the combination of EDS, FT-IR, and XPS analysis. The results of this study underscore the promising utility of BUT-12-3COOH as an effective sorbent for extracting radionuclides from environmental specimens and liquid nuclear waste streams. [ABSTRACT FROM AUTHOR]