Search

This work demonstrates that the packaging material commonly called "bubble wraps" (Aeroplast) can be leveraged to serve as a probe to visible sunlight exposure. This probe relies on a newly developed layered metal selenide photocatalyst with the general formula (DMAH)2xMnxSn3–xSe6 (DMSe‐1) (x = 1.3–1.7; DMAH+ = dimethylammonium), featuring a narrow bandgap of 0.76 eV, in addition to an indicator dye and a reducing agent. The photochemically sensitive probe is introduced into the air‐filled compartments of bubble wraps and undergoes photocatalytic degradation, resulting in a chromatic response to sunlight exposure. The probe's sensitivity to variable irradiation doses can be adjusted by varying the amount of the photocatalyst. The color intensity correlates with the absorbed irradiation dose, allowing for qualitative assessment by the naked eye or quantitative measurement using the RGB color system. The results obtained from the new probe agree with those obtained from standard sunlight pyranometers (r = 0.98), with an average error of <15%. This suggests that beyond their use as protective coatings, bubble wraps can be successfully repurposed as visible light sensors. Furthermore, this study describes the initial use of metal chalcogenides as visible light probes, potentially paving the way for the development of innovative light‐sensitive materials. [ABSTRACT FROM AUTHOR]

Environmental pollution has been a reality for many decades, with its contamination intensifying daily due to rapid urbanization and the ever-increasing world population. Dyes, and especially synthetic ones, constitute a category of pollutants that not only affect the quality of water but also exhibit high toxicity toward living organisms. This study was thoroughly planned to explore the removal of two toxic dyes, namely the methylene blue (MB) and methyl orange (MO) compounds from contaminated aqueous media. For this purpose, we designed and synthesized two new composite materials based on ammonium-functionalized Zr4+ MOF (MOR-1 or UiO-66-NH3+) and naturally occurring sorbents, such as bentonite and clinoptilolite. The composite materials displayed exceptional sorption capability toward both MB+ and MO− ions. A key finding of this study was the high efficiency of the composite materials to simultaneously remove MB+ and MO− under continuous flow conditions, also showing regeneration capability and reusability, thus providing an alternative to well-known mixed bed resins. [ABSTRACT FROM AUTHOR]

In the present study we provide the sorption properties of four 8-connected Zr4+ MOFs with the general formula H16[Zr6O16(RNH-BDC)4]·solvent (RNH-BDC2− = 2-alkyl-amine-terephthalate; R = ethyl-, ET-MOF; R = propyl-, PROP-MOF; R = isobutyl-, SBUT-MOF; R = n-butyl, BUT-MOF) towards toxic Cr(VI) and radionuclide-related ReO4− oxoanions. These MOFs represent superior sorbents for the removal of oxoanionic species, in terms of kinetics, sorption isotherms, selectivity and regeneration/reusability. The excellent sorption capability of the MOFs is due to a combination of surface and intra-framework sorption phenomena. The latter process proceeds via replacement of terminal water/hydroxyl ligands from the Zr6 clusters and subsequent binding of oxonanions to the Zr4+ centers, a fact that was proved via Rietveld PXRD analysis for the anion-loaded BUT-MOF. Importantly, BUT-MOF demonstrated an exceptional sorption capacity for Cr2O72− (505 mg g−1) and was further utilized in a sorption column in the form of MOF/calcium alginate beads, displaying remarkable removal efficiency towards industrial (chrome-plating) wastewater. Furthermore, the luminescence Cr(VI) sensing properties of BUT-MOF were explored in detail, presenting high sensitivity (detection limits as low as 9 ppb) and selectivity for these species against various competitive anions. [ABSTRACT FROM AUTHOR]

The use of terephthalate ligands with CnH2n+1NH-chains (n ≥ 6) led to the isolation of the first examples of Zr4+-terephthalate MOFs with 6-connected frameworks. The material with hexyl-amino functional groups has been proved to be an exceptional sorbent for the removal of As(III / V) toxic species from aqueous media, whereas MOFs with heptyl to dodecyl-amino moieties are superhydrophobic with promising oil–water separation properties. [ABSTRACT FROM AUTHOR]

Highly selective ion-exchange properties and exchange capacities of the open framework chalcogenide material [K.sub.6]Sn[[Zn.sub.4][Sn.sub.4][S.sub.17]] with [Cs.sup.+] and [NH.sub.4][.sup.+] are reported. An excellent model system in which ion-exchange processes and products, that could be characterized and studied in detail in various reactions stages is defined.

Zirconium(IV) metal organic frameworks (MOFs) with low net connectivity and available intra-framework sorption sites constitute excellent sorbents for toxic anions. To expand this family of highly promising sorbents, it would be desired to develop new synthetic strategies aiming towards such materials. Here we show that the utilization of terephthalate ligands with small to medium size alkyl-amino functional groups comprises an effective approach towards microporous Zr4+ MOFs with 8-connected frameworks. The new MOFs were proved the most effective Se(IV) and Se(VI) sorbents ever reported, with exceptional sorption capacities (up to 272 mgSe(IV) g−1 and 290 mgSe(VI) g−1), reusability, rapid sorption kinetics (≤3 min) and capability to sorb efficiently these anions in a very wide pH range (1–10), even in the presence of various competitive anions. The MOFs also display highly efficient sorption capability for the particularly toxic SeCN−, with such property demonstrated for the first time for MOF materials. [ABSTRACT FROM AUTHOR]