Metal–organic framework@silica as a stationary phase sorbent for rapid and cost-effective removal of hexavalent chromium

El-Mehalmey, Worood A.; Ibrahim, Ahmed; Abugable, Arwa A.; Hassan, Mohamed H.; Haikal, Rana R.; Karakalos, Stavros; Zaki, Omar; Alkordi, Mohamed H.

doi:10.1039/c7ta08281a

Cited by 115 publications

(61 citation statements)

References 64 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The weakest dispersive process P1 is visible below 220 K. With increasing temperature, the second process P2 enters our measurement frequency window in the 220-250 K temperature region and is superimposed by the strong response of the third process P3 at higher temperature. The real and imaginary parts of ε * start to decrease at about 350 K indicating dehydration of the samples [34]. This result is supported by the measurements of the temperature dependent weight loss of hydrated samples ( Figure S3), where a significant dehydration continues up to about 370 K. At slightly higher temperature the dielectric permittivity exhibits a sudden drop.…”

Section: Resultssupporting

confidence: 70%

Dielectric Spectroscopy of Water Dynamics in Functionalized UiO-66 Metal-Organic Frameworks

et al. 2020

View full text Add to dashboard Cite

We present a dielectric spectroscopy study of dipolar dynamics in the hydrated UiO-66(Zr) type metal-organic frameworks (MOFs) functionalized with −NH 2 and −F groups. Experiments are performed in a broad temperature and frequency ranges allowing us to probe several dipolar relaxations. For both samples at temperature below 220 K, we observe confined supercooled water dynamics, which can be described by the Arrhenius law. At slightly higher temperature, a second less pronounced dipolar relaxation is identified, and its origin is discussed. At even higher temperature, the dielectric permittivity exhibits anomalous increase with increasing temperature due to the proton conductivity. Upon further heating, the permittivity shows a sudden decrease indicating a reversible removal of water molecules. Measurements of the dehydrated samples reveal absence of all three dipolar processes.

show abstract

Section: Resultssupporting

confidence: 70%

Dielectric Spectroscopy of Water Dynamics in Functionalized UiO-66 Metal-Organic Frameworks

et al. 2020

View full text Add to dashboard Cite

show abstract

“…[7] For numerous usages of MOFs, the commonly isolated powder-form, consisting of μm-sized particles, is well suited, e. g. for gas storage [8] and water treatment applications. [9] However, a number of other emerging applications exploiting electrical and optical properties of MOFs [5] require high quality monolithic, pinhole-free thin films supported on solid substrates, [4] including coatings on fibers. [10] Well-defined thin films are also required for the fabrication of membranes for gasphase or liquid separation, [11] the construction of sensor devices, [12] the fabrication of optical, photovoltaic, and electronic devices, [13] as well as the use of MOF thin films in electrochemical applications.…”

Section: Liquid-phase Quasi-epitaxial Growth Of Highly Stable Monolimentioning

confidence: 99%

“…[7] For numerous usages of MOFs, the commonly isolated powder-form, consisting of μm-sized particles, is well suited, e. g. for gas storage [8] and water treatment applications. [9]…”

mentioning

confidence: 99%

Liquid‐Phase Quasi‐Epitaxial Growth of Highly Stable, Monolithic UiO‐66‐NH₂ MOF thin Films on Solid Substrates

et al. 2020

Self Cite

View full text Add to dashboard Cite

High quality, monolithic UiO-66-NH 2 thin films on diverse solid substrates have been prepared via a low temperature liquid phase epitaxy method. The achievement of continuous films with low defect densities and great stability against high temperatures and hot water is proven, clearly outperforming other reported types of MOF thin films.Metal-organic frameworks (MOFs) or porous coordination polymers (PCPs) represent a class of highly functional solid materials assembled from metal or metal/oxo nodes and di-or higher-topic organic linkers, [1,2] that continue to receive enormous attention. Due to their modular composition and the ability to access large number of topologies, [3] a huge number of different types of these porous materials, covering a broad spectrum of functionalities, has become available. In addition, combination of different types of Hetero-MOFs fabricated by employing heteroepitaxy via layer-by-layer procedures [4] allows the integration of several different functionalities in these materials, including electrical conductivity, [5] optical upconversion, [6] luminescent properties, and the ability to modulate electrical properties upon illumination with light. [7] For numerous usages of MOFs, the commonly isolated powder-form, consisting of μm-sized particles, is well suited, e. g. for gas storage [8] and water treatment applications. [9]

show abstract

“…At present, adsorption remains an effective method for Cr(VI) remediation [6], which involves the conversion from toxic Cr(VI) to mild Cr(III) in the adsorption process [7,8]. Various adsorbents have been developed, such as biochar [9,10], the metal-organic framework [11,12], nanoscale zero-valent iron [13,14], graphene oxide [15,16], and organic polymer [17,18]. Unfortunately, current adsorbents generally suffer from unsatisfactory removal capacity, a low adsorption rate, and weak reduction capacity.…”

Section: Introductionmentioning

confidence: 99%

Two-Dimensional Titanium Carbides (Ti3C2Tx) Functionalized by Poly(m-phenylenediamine) for Efficient Adsorption and Reduction of Hexavalent Chromium

Jin

Chai

Yang

et al. 2019

IJERPH

View full text Add to dashboard Cite

Titanium carbides (MXenes) are promising multifunctional materials. However, the negative surface charge and layer-by-layer restacking of MXenes severely restrict their application in the field of anionic pollutants, including in hexavalent chromium (Cr(VI)). Herein, Ti3C2Tx MXenes was functionalized through in situ polymerization and intercalation of poly(m-phenylenediamine) (PmPD), then Ti3C2Tx/PmPD composites were obtained. Delightedly, Ti3C2Tx/PmPD composites exhibited positive surface charge, expanded interlayer spacing, and enhanced hydrophobicity. Furthermore, the specific surface area of Ti3C2Tx/PmPD composite was five and 23 times that of Ti3C2Tx and PmPD, respectively. These advantages endowed Ti3C2Tx/PmPD composite with an excellent adsorption capacity of Cr(VI) (540.47 mg g−1), which was superior to PmPD (384.73 mg g−1), Ti3C2Tx MXene (137.45 mg g−1), and the reported MXene-based adsorbents. The Cr(VI) removal mechanism mainly involved electrostatic adsorption, reduction, and chelation interaction. This study developed a simple functionalization strategy, which would greatly explore the potential of MXenes in the field of anionic pollutants.

show abstract

Metal–organic framework@silica as a stationary phase sorbent for rapid and cost-effective removal of hexavalent chromium

Abstract: A one-pot synthesis is described to construct a composite of the amino-derivative Zr carboxylate metal–organic framework and silica gel (UiO-66-NH2@silica) as an efficient solid sorbent for hexavalent chromium.

Cited by 115 publications

References 64 publications

Dielectric Spectroscopy of Water Dynamics in Functionalized UiO-66 Metal-Organic Frameworks

Dielectric Spectroscopy of Water Dynamics in Functionalized UiO-66 Metal-Organic Frameworks

Liquid‐Phase Quasi‐Epitaxial Growth of Highly Stable, Monolithic UiO‐66‐NH₂ MOF thin Films on Solid Substrates

Two-Dimensional Titanium Carbides (Ti3C2Tx) Functionalized by Poly(m-phenylenediamine) for Efficient Adsorption and Reduction of Hexavalent Chromium

Contact Info

Product

Resources

About

Metal–organic framework@silica as a stationary phase sorbent for rapid and cost-effective removal of hexavalent chromium

Abstract: A one-pot synthesis is described to construct a composite of the amino-derivative Zr carboxylate metal–organic framework and silica gel (UiO-66-NH2@silica) as an efficient solid sorbent for hexavalent chromium.

Cited by 115 publications

References 64 publications

Dielectric Spectroscopy of Water Dynamics in Functionalized UiO-66 Metal-Organic Frameworks

Dielectric Spectroscopy of Water Dynamics in Functionalized UiO-66 Metal-Organic Frameworks

Liquid‐Phase Quasi‐Epitaxial Growth of Highly Stable, Monolithic UiO‐66‐NH2 MOF thin Films on Solid Substrates

Two-Dimensional Titanium Carbides (Ti3C2Tx) Functionalized by Poly(m-phenylenediamine) for Efficient Adsorption and Reduction of Hexavalent Chromium

Contact Info

Product

Resources

About

Liquid‐Phase Quasi‐Epitaxial Growth of Highly Stable, Monolithic UiO‐66‐NH₂ MOF thin Films on Solid Substrates