Zr-based UiO-66 metal–organic framework (MOF) is one of the most studied MOFs with a wide range of potential applications. While UiO-66 is typically synthesized as a microcrystalline solid, we employ a particle downsizing strategy to synthesize UiO-66 as fluid gel with unique rheological properties, which allows the solution-based processing as sub-100 nm films and enhances the electrical conductivity of its pristine structure. Film thicknesses ranging from 40 to 150 nm could be achieved by controlling the spin-coating parameters. The generality of the method is also demonstrated for other Zr-based MOFs including MOF-801 and MOF-808. The impact of particle size and film thickness at the nanoscale on electrical properties of UiO-66 is shown to realize new features that are distinct from those of the bulk powder phase. An electrical insulator UiO-66 shows a significant increase in the electrical conductivity (10–5 S cm–1 compared to 10–7 S cm–1 in the bulk powder phase) when the 10 nm particles are distributed on the substrate with a thickness less than 100 nm. The findings establish a new route for processing of MOF materials as thin films with fine-tuned thickness and offer a new perspective for transport properties of Zr-based MOFs without structural modification.

Zirconium clusters of UiO-66 have been hydroxylated with NaOH to generate strong binding sites for As­(III) species in wastewater treatment. Hydroxylated UiO-66 provides high adsorption capacity over a wide range of pH from 1 to 10 with a maximum uptake of 204 mg g–1, which is significantly enhanced compared to those of pristine UiO-66, acid-modulated UiO-66, and other adsorbents for use in a wide pH range of treatment processes. The local structure of hydroxylated sites and As­(III) adsorption mechanism are determined by extended X-ray absorption fine structure combined with density functional theory calculations.

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The UiO-66-NH2 aerogel has been designed to remove As­(III) and As­(V) in the full pH range with a long lifetime. The efficiency of the aerogel for trace removal from river water samples at the sub-ppb level has been demonstrated. The feasibility for practical uses has been evaluated by breakthrough experiments operated at a liquid hourly space velocity (LHSV) of 38 h–1 using a real water sample with a significant capacity of 284 mg g–1. The UiO-66-NH2 aerogel provides a lifetime of over 600 min, which is one of the highest lifetimes among the reported adsorbents for arsenic decontamination.

This study is focused on the characterization of polyethylene terephthalate (PET)/Styrene-Ethylene-Butylene-Styrene (SEBS)/Organomontmorillonite (OMMT) blends. SEBS-g-MA is used as compatibilizer and SEBS is the impact modifier at 30 %wt. The compounds were blended by twin-screw extruder and molded for test specimen by injection molding. The effect of OMMT types (Cloisite15A and Cloisite30B) and contents (1 and 3 %w/w) on properties of PET blends with SEBS and SEBS-g-MA were investigated. The PET composites incorporated with Cloisite15A had higher impact strength and %elongation at break whereas lower tensile strength than the one with Cloisite30B. Comparing with PET/SEBS/SEBS-g-MA blends, adding OMMT into PET/SEBS/SEBS-g-MA would increase thermal property. However, it had no significant changes with higher OMMT. %Crystallinity of PET would be increased with OMMT contents. PET/SEBS/SEBS-g-MA had lower %LOI but higher burning rate compared with PET. However, the addition of OMMT could improve flame retardant properties of PET blends. Addition of Cloisite15A and Cloisite30B into PET/SEBS/SEBS-g-MA increased %LOI. From UL 94 tests, polymer composites could be classified in HB class. The burning rate of polymer composites was decreased with increasing OMMT due to decomposition of OMMT act as a barrier to inhibit combustion.