Publications by authors named "Biplab Joarder"

The current paradigm considers the control of the MOF/polymer interface mostly for achieving a good compatibility between the two components to ensure the fabrication of continuous mixed-matrix metal-organic framework (MMMOF) membranes. Here, we unravel that the interfacial pore shape nanostructure plays a key role for an optimum molecular transport. The prototypical ultrasmall pore AlFFIVE-1-Ni MOF was assembled with the polymer PIM-1 to design a composite with gradually expanding pore from the MOF entrance to the MOF/polymer interfacial region.

View Article and Find Full Text PDF

Membrane technology, regarded as an environmentally friendly and sustainable approach, offers great potential to address the large energy penalty associated with the energy-intensive propylene/propane separation. Quest for molecular sieving membranes for this important separation is of tremendous interest. Here, a fluorinated metal-organic framework (MOF) material, known as KAUST-7 (KAUST: King Abdullah University of Science and Technology) with well-defined narrow 1D channels that can effectively discriminate propylene from propane based on a size-sieving mechanism, is successfully incorporated into a polyimide matrix to fabricate molecular sieving mixed matrix membranes (MMMs).

View Article and Find Full Text PDF

Water contamination due to heavy metal-based toxic oxo-anions (such as CrO and TcO) is a critical environmental concern that demands immediate mitigation. Herein, we present an effort to counter this issue by a novel chemically stable cationic metal-organic framework (iMOF-2C) with strategic utilization of a ligand with hydrophobic core, known to facilitate such oxo-anion capture process. Moreover, the compound exhibited very fast sieving kinetics for such oxo-anions and a very high uptake capacity for CrO (476.

View Article and Find Full Text PDF

Selectively capturing toxic oxoanions of selenium and arsenic is highly desired for the remediation of hazardous waste. Ionic metal-organic frameworks (iMOFs) especially cationic MOFs (iMOF-C) as ion-exchange materials, featuring aqueous phase stability, present a robust pathway for sequestration of the oxoanions owing to their ability to prevent leaching because of their ionic nature. On account of scarcity of water-stable cationic MOFs, the capture of oxoanions of selenium and arsenic has been a major challenge and has not been investigated using iMOFs.

View Article and Find Full Text PDF

An isostructural pair of extremely rare, permanently microporous sulfonate-based metal-organic frameworks (MOFs) having a novel topology has been reported here by integration of rationally chosen building units. The compounds bear polar sites in the pore surfaces and exhibit selective adsorption of CO, which features among the highest reported uptakes in the domain of organosulfonate-based MOFs. The compounds also exhibit multifunctionality for C-cyclic hydrocarbon separation and selective detection of neurotransmitter nitric oxide.

View Article and Find Full Text PDF

Triplet-triplet annihilation-based photon upconversion (TTA-UC) is a process wherein longer-wavelength light (lower-energy photons) is converted into shorter-wavelength light (higher-energy photons) under low excitation intensity in multichromophore systems. There have been many reports on highly efficient TTA-UC in solution; however, significant challenges remain in the development of solid-state upconverters in order to explore real-world applications. In this Perspective, we discuss the advantages and challenges of different approaches for TTA-UC in solvent-free solid systems.

View Article and Find Full Text PDF

Two complementary design strategies, isomorphous ligand replacement and heterocycle doping, have been applied to iteratively enhance the proton conductivity of a metal-organic framework, β-PCMOF2. The resulting materials, PCMOF2/(Pz) and PCMOF2/(Tz) (Pz = 1H-pyrazole, Tz = 1H-1,2,4-triazole), have their proton conduction raised almost 2 orders of magnitude compared to β-PCMOF2. The bulk conductivities of these materials are over 10 S cm at 85 °C and 90% relative humidity (RH), while maintaining the parent MOF structure.

View Article and Find Full Text PDF

A sulfonated indium (In) metal organic framework (MOF) is reported with an anionic layered structure incorporating hydrogen-bonded dimethylammonium cations and water molecules. The MOF becomes amorphous in >60% relative humidity; however, impedance analysis of pelletized powders revealed a proton conduction value of over 10 S cm at 25 °C and 40% RH, a very high proton conduction value for low humidity and moderate temperature. Given the modest humidity stability of the MOF, triaxial impedance analyses on a single crystal was performed and confirmed bulk proton conductivity over 10 S cm along two axes corroborating the data from the pellet.

View Article and Find Full Text PDF

A pure aqueous phase recognition and corresponding detoxification of highly toxic cyanide ions has been achieved by a fluorescent metal-organic framework (MOF). The cyanide detoxification has been shown to be effective even in in vitro studies and the MOF could be recycled to show the same efficiency of detoxification.

View Article and Find Full Text PDF

The separation of styrene and ethylbenzene mixtures is industrially important and is currently performed in highly energy-intensive vacuum distillation columns. The primary objective of our investigation is to offer an energy-efficient alternative for selective adsorption of styrene by a flexible metal-organic framework, DynaMOF-100. The structural transformation of DynaMOF-100 is specifically triggered on inclusion of styrene within the framework; this structural transformation is reversible.

View Article and Find Full Text PDF

A novel porous metal-organic framework (MOF) architecture is formed by a neutral amide-functionalized ligand and copper(II). Upon desolvation, this compound undergoes a dynamic structural transformation from a one-dimensional (1D) porous phase to a two-dimensional (2D) non-porous phase that shows selective uptake of benzene over cyclohexane. The as-synthesized compound also acts as a visual colorimetric anion sensor for thiocyanate.

View Article and Find Full Text PDF

Highly selective and sensitive aqueous-phase detection of nitro explosive 2,4,6-trinitrophenol (TNP) by a hydrolytically stable 3D luminescent metal-organic framework is reported. The compound senses TNP exclusively even in the presence of other nitro-compounds, with an unprecedented sensitivity in the MOF regime by means of strategic deployment of its free amine groups. Such an accurate sensing of TNP, widely recognized as a harmful environmental contaminant in water media, establishes this new strategic approach as one of the frontiers to tackle present-day security and health concerns in a real-time scenario.

View Article and Find Full Text PDF

A three-dimensional cationic framework based on a flexible neutral nitrogen-donor ligand was synthesized and undergoes guest-driven structural dynamics in a reversible way. Size-selective anion-exchange and tunable luminescent behavior of the framework has been explored.

View Article and Find Full Text PDF

A 3D dynamic coordination framework with an electron-deficient pore surface has been synthesized by using Zn(II) (having a variable coordination number) and a predesigned flexible π-electron-deficient core-based ligand, exhibiting chemical separations based on pore surface functionalization (π Lewis acidic pore surfaces and open metal sites) and framework flexibility, giving rise to a unique smart guest-responsive material.

View Article and Find Full Text PDF

Reaction of a linear bi-chelating N-donor achiral ligand with Zn(II) afforded a homochiral cationic framework with six-fold one-dimensional helical chains. The compound showed selective anion exchange behavior with interesting anion-responsive tunable bulk-phase homochirality. The cationic framework also presented anion-driven variable luminescence and sorption behavior.

View Article and Find Full Text PDF

Chemical separation has great importance in industrial applications. Separation of xylene isomers still prevails to be one of the most important challenges in chemical industry, due to the large amount of commercial use of p-xylene in the production of beverage bottles, fibers and films. A novel Zn(II)-based dynamic coordination framework based on flexible ether-linkage, exhibiting selective adsorption of p-Xylene over its congener C8-alkyl aromatic isomers at ambient conditions is reported.

View Article and Find Full Text PDF

Two new hexanuclear symmetric dysprosium wheels, namely, [Dy6(L1)6(L')6(OCH3)6(2CH3OH)] and [Dy6(L2)6(L')6(OCH3)6(2CH3OH)] (L1H = pivalic acid and L2H = 3,5-dinitrobenzoic acid, L'H= 2,6-dimethoxyphenol) were isolated employing a mixed-ligand strategy. The strategic introduction of two different auxiliary groups with diverse steric effects and electrostatic actions affect the magnetic coupling and local anisotropy of Dy(III) ion, therefore exhibiting dissimilar magnetic behaviors.

View Article and Find Full Text PDF

Assimilation of open metal sites (OMSs) and free functional organic sites (FOSs) with a framework strut has opened up a new route for the fabrication of novel metal-organic materials, thereby providing a unique opportunity to explore their multiple functionalities. A new metal-organic framework (MOF), {[Cu(ina)2(H2O)][Cu(ina)2(bipy)]·2H2O}n (1) (ina=isonicotinate, bipy=4,4'-bipyridine), has been synthesized and characterized. Complex 1 is crystallized in the orthorhombic noncentrosymmetric space group Aba2 and consists of two different 2D coordination polymers, [Cu(ina)2(H2O)]n and [Cu(ina)2(bipy)]n, with entrapped solvent water molecules.

View Article and Find Full Text PDF

A three-dimensional biporous soft porous coordination polymer containing active coordination space, made of cadmium(II) and a tripodal carboxylate ligand bearing ether linkages, was synthesized and characterized. Guest-dependent dynamic activities in the active coordination space of the soft porous crystal have been explored. We have demonstrated controlled chemical blocking and unblocking of active pores of the dynamic framework along with guest-dependent contraction and expansion of the channels by single-crystal-to-single-crystal structural transformation studies.

View Article and Find Full Text PDF

On the move: Two isostructural, homochiral Cu(II) coordination frameworks based on amino acids (D- and L-PGA) were synthesized. Dynamic behavior by solid-state structural transformation in single-crystal-to-single-crystal fashion was demonstrated. The extent of structural dynamism was shown by guest inclusion studies.

View Article and Find Full Text PDF

Two discrete nitrate-bridged novel "pseudo-double-propeller"-shaped hexanuclear Cu/Ln clusters of the formula [Cu(4)Ln(2)L(4)L'(4)(NO(3))(2)(OH(2))(2)]·3NO(3)·4H(2)O [Ln = Dy, Gd; LH = o-vanilin; L'H = 2-(hydroxyethyl)pyridine] were synthesized and characterized. Single-crystal X-ray diffraction studies revealed the trimeric half-propeller-type Cu(2)/Ln core connected to other opposite-handed similar trimers by a bridging nitrate ligand. The Dy analogue, [Cu(4)Dy(2)L(4)L'(4)(NO(3))(2)(OH(2))(2)]·3NO(3)·4H(2)O, shows frequency-dependent out-of-phase alternating-current magnetic susceptibility, which indicates that this novel discrete [Cu(4)Dy(2)] heterometallic cluster may exhibit single-molecule-magnet behavior.

View Article and Find Full Text PDF

Herein, we present a carboxylate-based dinuclear dysprosium compound, namely [Dy(2)L(6)(MeOH)(2)(H(2)O)(2)] (LH = n-butyric acid) from the reaction of Dy(NO(3))(3)·xH(2)O with n-butyric acid and triethylamine in MeOH solvent. The single crystal X-ray diffraction analysis demonstrate that a total of six monocarboxylate ligands formed this dimeric compound by carboxylate bridging along with coordination from solvent molecules (water and methanol). Each Dy(III) ion is coordinated by nine donor atoms forming a mono-capped antiprismatic coordination environment.

View Article and Find Full Text PDF

A homochiral luminescent porous coordination polymer, [Cd(L)(H(2)O)]·3H(2)O, with interconnected collagen like triple-helical chains has been synthesized solvothermally by using cadmium(II) salt and a newly designed d-isosorbide-based, enantiomerically pure chiral ligand. The framework is a 2D porous material and forms a 1D channel along the a axis, with the channel dimensions ~6.2 × 4.

View Article and Find Full Text PDF