Benzene Tricarboxylate Research Articles

Mixed precious-group metal-organic frameworks: a case study of the HKUST-1 analogue [RuxRh3-x(BTC)2

This work presents the first full series of mixed precious-group metal-organic frameworks (MPG-MOFs) using ruthenium and rhodium. The obtained crystalline, highly porous and thermally robust materials were characterized by means of powder X-ray diffraction, N2/CO2 sorption isotherms, thermogravimetry, spectroscopy methods (IR, Raman, UV/VIS-, NMR and XPS) and as well by high resolution transmission electron microscopy (HR-TEM) with elemental mapping (HAADF-EDS). Additionally, the assignment of spectroscopic data is supported by computational (time dependent)-density functional theory methods. The materials turned out to consist of homogeneously dispersed Ru2 and Rh2 paddlewheel units being linked by benzenetricarboxylate (BTC) to yield a framework that is isoreticular to [Cu3(BTC)2] (HKUST-1, Hong Kong University of Science and Technology). However, acetate (OAc) is incorporated as an intrinsic component which compensates for missing BTC-linker defects and some Cl is coordinated to the Ru centre at an apical position. The exact empirical formula of the MPG-MOFs is derived as [RuxRh3-x(BTC)2-a(OAc)b(Cl)c].

Cu2+-BTC based metal–organic framework: a redox accessible and redox stable MOF for selective and sensitive electrochemical sensing of acetaminophen and dopamine

A Cu2+ plus benzenetricarboxylate (BTC) based ‘3D’ metal–organic framework HKUST-1 was synthesized via a facile microwave assisted route.

Metal-Organic Frameworks Mediate Cu Coordination for Selective CO2 Electroreduction.

The electrochemical carbon dioxide reduction reaction (CO2RR) produces diverse chemical species. Cu clusters with a judiciously controlled surface coordination number (CN) provide active sites that simultaneously optimize selectivity, activity, and efficiency for CO2RR. Here we report a strategy involving metal-organic framework (MOF)-regulated Cu cluster formation that shifts CO2 electroreduction toward multiple-carbon product generation. Specifically, we promoted undercoordinated sites during the formation of Cu clusters by controlling the structure of the Cu dimer, the precursor for Cu clusters. We distorted the symmetric paddle-wheel Cu dimer secondary building block of HKUST-1 to an asymmetric motif by separating adjacent benzene tricarboxylate moieties using thermal treatment. By varying materials processing conditions, we modulated the asymmetric local atomic structure, oxidation state and bonding strain of Cu dimers. Using electron paramagnetic resonance (EPR) and in situ X-ray absorption spectroscopy (XAS) experiments, we observed the formation of Cu clusters with low CN from distorted Cu dimers in HKUST-1 during CO2 electroreduction. These exhibited 45% C2H4 faradaic efficiency (FE), a record for MOF-derived Cu cluster catalysts. A structure-activity relationship was established wherein the tuning of the Cu-Cu CN in Cu clusters determines the CO2RR selectivity.

The Largest Supertetrahedral Oxychalcogenide Nanocluster and Its Unique Assembly.

Supertetrahedral oxychalcogenide T n nanoclusters (NCs, n denotes the number of metal-chalcogen layers) integrate chemically distinct but ordered oxygen and chalcogen sites in zinc-blend-type "quantum dots". They therefore offer a new level of control over various properties of semiconducting materials. So far, few such structures are known, and the cluster size is also limited to only T4 with 20 metal sites. Herein, we report an unusual oxysulfide T5 nanocluster with 35 metal sites. It has unprecedented In-O@In-S "core-shell" nanostructure and is also the largest supertetrahedral oxychalcogenide NC. Through cocrystallization, we further demonstrate that such oxychalcogenide NCs can be assembled to form multidimensional structures. In addition to N-donor imidazolates that help to form a 3-D structure with chiral quartz net, the O-donor benzenetricarboxylate (BTC) has also been found to successfully organize such T5 NCs. It is worth noting that no carboxylate ligands have been shown earlier for assembling chalcogenide clusters, despite their prevalence in MOFs. Given the wide availability of O-donor ligands, this work introduces a versatile platform with promise for a new generation of semiconducting inorganic-organic hybrid materials.

Charge Transport, Conductivity, and Carrier Density in Tcnq Loaded MOF Films

Bulk Metal-organic-framework (MOF) films are designed scaffold-like compounds that consist of metal ions connected by organic ligands in the form of crystalline powders, while Surface Anchored Metal-organic-framework (SURMOF) films consist of quasi-liquid phase epitaxially grown highly ordered crystalline films. The ability to conduct electrical charge is one of the most important but least understood properties of MOF films and coordination network materials. Very little work exists on electrical characterization of MOF films, because the early synthesized pristine MOF films exhibited mostly insulating characteristics. Recently, it has been reported that the electrical properties of bulk host MOF films can be modulated by infiltrating guest molecules (metal clusters) inside the porous MOF framework. This renders MOF materials a novel and potentially promising material for microelectronic devices, sensors, and thermoelectrics. For this case study we used MOF Cu3(BTC)2 (BTC: benzene tricarboxylate) films, also known as HKUST-1 (Hong Kong University of Science and Technology-1), which were infiltrated with tetracyano-quinodimethane (TCNQ) guest molecules to modulate the charge transport characteristics. HKUST-1 MOF thin films have been grown using a liquid phase epitaxy (LPE) spray method in which the metal-containing solution [1 mmol Cu(OAc)2] and the linker solution [0.1 mmol BTC] are sprayed alternately on modified silicon substrates. Subsequently, the samples were immersed into an ethanoic TCNQ solution. For benchmarking we have investigated the electrical characteristics of pristine HKUST-1 and TCNQ loaded compact HKUST-1 SURMOF films by Hall-Effect measurements and Seebeck measurements. Both Hall Effect and Seebeck coefficient measurements indicate that electrical conduction in dense compact MOF films involves positive charge carriers. The Hall coefficient, mobility as well as the charge carrier density, the electrical conductivity and the sheet resistance for HKUST-1 MOF films will be discussed.

The Thermal Properties of Pristine and Loaded HKUST-1 Thin Films Under Different Environmental Conditions

Metal Organic Frameworks (MOFs) may prove as useful materials for the improvement of the efficiency of thermoelectrics. An improved Figure of Merit could be realized by taking advantage of the intrinsically low thermal conductivity of their porous organic makeup and improving the electrical conductivity by infiltrating the pores with selective host molecules. This study experimentally examines the thermal properties of HKUST-1 Metal Organic Framework (MOF) thin films using Time Domain Thermoreflectance (TDTR). The time scale associated with TDTR allows for a valid representation of thermal transport within the solid network of the porous composite. The MOF thicknesses vary from 200-350 nm and are constructed from Cu++ dimers and benzene-tricarboxylate (BTC) units which form a crystalline, 3-D porous structure with a pore diameter of 1.2 nm. The available pores allow the loading or storage of guest molecules, such as tertracyanoquin odimethane (TCNQ). We find evidence of no size effects on the thermal conductivity of the thin MOF films with thicknesses ranging from 200 – 350 nm. Additionally, the introduction of TCNQ host molecules within the infiltrated MOF does not significantly alter the thermal conductivity compared to the pristine samples. Exposure to ambient atmosphere causes an increase in the thermal conductivity of both the pristine and infiltrated MOFs, indicating that water adsorption may be occurring and altering the thermal properties of these materials. Activation of the pristine MOF recovers the thermal conductivity of the ideal state (before exposure to an ambient air environment) showing further application of these materials as a thermal switch.

From powder to cloth: Facile fabrication of dense MOF-76(Tb) coating onto natural silk fiber for feasible detection of copper ions

The deposition of powdered MOFs material onto other substrates is essential to avoid inconvenience during its practical applications. In this work, domestic silk fiber was utilized as the skeleton, for successful coating of dense luminescent MOF-76(Tb). Its surface functionality which consist of abundance of intrinsic carboxylic groups, smooth surface structure, and 80% of tensile strength were maintained after being immersed in different thermal solvents (water, ethanol, DMF @ 80 °C) for 24 h, revealing good solvent and thermal resistance. By using hydrothermal, microwave assisted, and layer-by-layer methods, different crystal morphologies (pillar-like, sedimentary-rock-like, and needle-like morphology) and varying degrees of surface coverage rate were obtained, as a result of different levels of anchoring promotion and crystal controlling effect. The MOFs coating can be confirmed by its XRD pattern and fluorescent property. More importantly, the quenching effect of the composite in a condition of Cu2+ was first reported with high selectivity, sensitivity (i.e. a linear detection concentration range of 10−3–10−5 M with a low detection limit up to 0.5 mg/L, KSV of 1192 M−1 at 293 K), and rapid response time (5 min), making the composite a good candidate for colorimetric and fluorescent detection of aquatic Cu2+. The quenching mechanism is proposed to associate with the interaction between Cu2+ and benzene-tricarboxylate (BTC) ligand, which resulted in the decrease of energy transfer efficiency. The selectivity over other common cations depends on the unsaturated electron configuration and the smaller ionic radius of Cu2+.

Polycarboxylate-Templated Coordination Polymers: Role of Templates for Superprotonic Conductivities of up to 10-1 S cm-1.

Three coordination polymers (CPs) have been synthesized based on a [Co(bpy)(H2 O)4 ]2+ chain (bpy=4,4'-bipyridine) by a template approach. The frameworks are neutralized by different templated polycarboxylate anions (furan di-carboxylate (fdc) in Co-fdc, benzene tri-carboxylate (btc) in Co-tri and benzene tetra-carboxylate (btec) in Co-tetra). These templates with different degrees of protonation and ionic carrier concentration played significant role on crystal packing as well as formation of well-directed H-bonded networks which made these CPs perform well in proton conduction (PC). The PC value reaches to 1.49×10-1 S cm-1 under 80 °C and 98 % relative humidity (R.H.) for Co-tri, which is the highest among CPs/MOFs/COFs and is an example of conductivity in the order of 10-1 S cm-1 . Co-tri and Co-tetra are excellent proton conductors at mild temperature (40 °C) and 98 % R.H. (conductivities up to 2.92×10-2 and 1.38×10-2 S cm-1 , respectively).

Thermoelectric Properties of Metal-Organic-Framework Thin Films

Bulk Metal-Organic-Framework (MOF) films are designed scaffold-like compounds which are composed by inorganic metal clusters connected with organic linker molecules, forming highly ordered, crystalline and porous structures. These bulk MOF frameworks were initially designed for gas storage due to their high storage capacity inside the pores of MOF bulk materials. However, the application for electrical devices were very limited resulting from their insulating character. Recently, it has been reported that the electrical properties of bulk host MOFs can be modulated by infiltrating guest molecules (metal clusters) inside the porous MOF framework. This renders MOF materials a novel and promising material for microelectronic devices, sensors, catalytically active materials and thermoelectrics. In our work, oriented SURMOF films and random polycrystalline MOF films Cu3(BTC)2 (BTC: benzene tricarboxylate, known as HKUST-1 MOF, were synthesized by a liquid phase epitaxy (LPE) spray method grown on surface functionalized gold coated silicon substrates and regular non-functionalized silicon substrates covered with a thick 484 nm thermal SiO2 layer respectively. The tetracyano-quinodimethane (TCNQ) guest molecules were infiltrated into the MOFs to modulate the electrical properties of the film. The horizontal Seebeck coefficient parallel to the sample surface of both oriented SURMOF films and random polycrystalline MOF films were measured. The random oriented MOF films exhibit a high positive Seebeck coefficient of 422.32 µV/K at 350 K. However, the horizontal Seebeck coefficient of oriented SURMOF films fluctuates around 0 µV/K. This can be interpreted that these highly oriented SURMOF films exhibit a large anisotropy with no charge carrier transport in horizontal direction parallel to the sample surface, but only carrier transport in vertical direction. The anisotropic nature of SURMOF films were further proven by IV characterization. The electrical conductivity of polycrystalline MOF film in horizontal direction was observed in the temperature range of 260 K to 350 K to calculate power factor (S2δ) of MOF films. The maximum value of power factor was found at 350 K about 1.527 µW/(m2K), which is about one order of magnitude higher than reported one. The thermal conductivity measurement on polycrystalline MOF films indicated the TCNQ infiltration not only contributes to enhance electrical conductivity, but also results in a reduction of thermal conductivity of MOF films. The reduced thermal conductivity can be attributed to enhanced phonon scattering due to TCNQ infiltration. The results demonstrate that random polycrystalline MOF film has a promising application potential in future thermoelectric and electronic devices.

Enhancement of the Water Adsorptivity of Metal–Organic Frameworks upon Hybridization with Layered Double Hydroxide Nanosheets

Efficient water adsorbents with improved hydrostability can be synthesized by the hybridization of metal–organic framework (MOF) compounds with exfoliated layered double hydroxide (LDH) 2D nanosheets. The self-assembly between copper benzene tricarboxylate (Cu-BTC) MOF nanocrystals and exfoliated Mg–Al-LDH nanosheets leads to the nanoscale mixing of the MOF and LDH components, as well as to the prevention of the formation of aggregated secondary MOF particles. In the resulting nanohybrids, spherical Cu-BTC nanocrystals with small particle sizes of ∼5–10 nm are uniformly anchored on the surface of Mg–Al-LDH 2D nanosheets with the dimensions of several hundred nanometers. At the optimal composition, the surface area of the resulting nanohybrid becomes greater than that of pristine Cu-BTC, which is attributable to the suppression of the self-aggregation of MOF nanocrystals and to the formation of the mesoporous stacking structure of the LDH nanosheets. Of prime importance is that both the water adsorption ab...

Synthesis and Transport Properties of Novel MOF/PIM-1/MOF Sandwich Membranes for Gas Separation.

Metal-organic frameworks (MOFs) were supported on polymer membrane substrates for the fabrication of composite polymer membranes based on unmodified and modified polymer of intrinsic microporosity (PIM-1). Layers of two different MOFs, zeolitic imidazolate framework-8 (ZIF-8) and Copper benzene tricarboxylate ((HKUST-1), were grown onto neat PIM-1, amide surface-modified PIM-1 and hexamethylenediamine (HMDA) -modified PIM-1. The surface-grown crystalline MOFs were characterized by a combination of several techniques, including powder X-ray diffraction, infrared spectroscopy and scanning electron microscopy to investigate the film morphology on the neat and modified PIM-1 membranes. The pure gas permeabilities of He, H2, O2, N2, CH4, CO2 were studied to understand the effect of the surface modification on the basic transport properties and evaluate the potential use of these membranes for industrially relevant gas separations. The pure gas transport was discussed in terms of permeability and selectivity, highlighting the effect of the MOF growth on the diffusion coefficients of the gas in the new composite polymer membranes. The results confirm that the growth of MOFs on polymer membranes can enhance the selectivity of the appropriately functionalized PIM-1, without a dramatic decrease of the permeability.

Highly Efficient Yttrium Based Metal Organic Framework for Removal of Pollutant Dyes

Highly porous crystalline luminescent metal Organic Frameworks (MOFs) were synthesized by conjugating Yttrium nitrate and Benzene Tri Carboxylate (BTC) in the presence of surfactant Cetyl Tri methyl Ammonium Bromide. A characteristic blue emission peak around 400 nm of Y upon excitation with UV light and peaks through Infra-Red spectroscopy revealed the formation of co-ordinate bond between Y and BTC, thereby confirming the formation of MOF nanoparticles (NPs). The nanoparticles were studied for potential removal of pollutants by encapsulation of the dye methylene blue (MB). Optical analysis affirmed the encapsulation of dye particles within the porous MOF NPs as dye absorption decreased around 600nm. This study offers great promise of using MOF NPs as platform for sensing of analytes in solution and removal of pollutant materials.

Synthesis of Iron Based Biocompatible Metal Organic Frameworks for Microencapsulation of Docetaxel

Tunable properties of porous metal organic frameworks (MOFs) make them a potential candidate for sustained release of functionally active biomolecules. Current study describes in situ encapsulation of anti-cancer drug, docetaxel in iron based MOFs for drug delivery applications. MOFs were synthesized using emulsification approach by mixing FeCl3.4H2Oand benzene tricarboxylate (BTC) in 1:1 molar ratio in the presence of cetyl trimethyl ammonium bromide (CTAB). Optical characterization of the NMOFs was done using UV-visible and FTIR spectroscopy. The peak obtained at 265 nm in the UV-visible spectrum indicated the formation of iron-based NMOF. The peaks obtained at 3416, 1623 and 3343cm-1 corresponding to C=O, C=C and C=O groups in FTIR spectroscopy further supported our observations. Microencapsulation of docetaxel was achieved by mixing the drug with the iron salt during the synthesis of MOF. Drug encapsulation was affirmed by Transmission Electron Microscopy. Current study is an attempt in exploring the microencapsulation properties of MOFs.

Thermoelectric Properties of Highly Ordered Metal-Organic Framework Films

Surface Anchored Metal-organic-framework (SURMOF) films are designed quasi-crystalline compounds that consists of metal ions connected by organic ligands, forming highly ordered porous structures. The SURMOF films initially were considered to have limited applications in electronic devices because of their insulating character. Recently, several approaches were found to tune the electrical conductivity of MOFs [1]. One of the effective methods found is to infiltrate guest molecules inside the porous framework to transport ions, and hence to modulate the electrical properties of the host framework. MOF Cu3(BTC)2 (BTC: benzene tricarboxylate) is a typical MOF film known as HKUST-1 (Hong Kong University of Science and Technology 1). Its electrical conductivity could increase up to 7 orders of magnitude by introducing tetracyano-quinodimethane (TCNQ) guest molecules. Recently MOFs films received more attention in the fields of switching nanodevices [2], sensors, and thermoelectrics. reported MOF films loaded with TCNQ@Cu3(BTC)2 exhibiting high Seebeck coefficients and low thermal conductivity [3]. However, the low electrical conductivity reduces the figure of merit ZT of MOFs. In this work we present alternating MOF/PbTe and MOF/PbSe nanolaminate structure synthesized by alternately depositing SURMOF films and lead chalcogenide films. The SURMOFs were fabricated by liquid phase epitaxy (LPE) technique. Ethanoic solution of copper acetate hydrate (1mM) and organic linker solution (1, 3, 5-benzenetricarboxylic acid) (0.2mM) were used as precursors for HKUST-1 MOFs. TCNQ was loaded to modulate electrical conductivity of MOFs. PbTe and PbSe were synthesized on the top of MOFs by thermal ALD technology. Lead bis(2,2,6,6-tetramethyl-3,5-heptanedionato) (Pb(C11H19O2)2), (trimethylsilyl) telluride ((Me3Si)2Te) and (trimethylsilyl) selenide ((Me3Si)2Se) were employed as the chemical ALD precursors for lead, telluride and selenide, respectively. 20 sccm N2 was used as a carrier gas to transport the chemical precursors into the ALD reaction chamber. The ALD growth temperature was 150 ˚C. The solid lead precursor was volatilized at a temperature of 170 ˚C, the liquid Te precursor required heating to 40 ˚C, and the liquid Se precursor was kept at room temperature. The chamber base pressure was kept at 30 mTorr. Composite nanolaminate structure of MOF/PbTe and MOF/PbSe with film thickness of 10 nm/ 10 nm, 20 nm/ 20 nm, and 60 nm/ 60 nm were fabricated and investigated. Several physical characterization techniques have been employed to determine the surface characters of the sample. The samples were characterizated by X-ray diffraction (XRD) for film crystal structure, and by field emission scanning electron microscopy (FE-SEM) for film morphology and structure. For thermoelectrical properties of the sample, Seebeck coefficient both in vertical and horizontal directions were measured. Electrical conductivity and thermal conductivity of the films were investigated as well to envaluate ZT value of the samples. Figure 1 shows the IV characteristics of MOF films loaded with TCNQ. The linear IV curve indicates Ohmic conduction in TCNQ loaded MOFs. Figure 2 displays the Seebeck coefficient of TCNQ loaded MOF films over a temperature range of 290 K ~330 K. The maximum Seebeck coefficient of the film occurs at 290 K and the positive Seebeck coefficient reveals positive charge carriers in the MOF film.

Synthesis and characterization of a new anionic zinc-adeninate metal–organic framework, [Zn3(ad)(BTC)2·(Me2NH2), 5.75 DMF, 0.25 H2O

A new anionic zinc-adeninate metal–organic framework, [Zn3(ad)(BTC)2·(Me2NH2), 5.75DMF, 0.25H2O] (ad = adeninate; BTC = benzene tricarboxylate; DMF = dimethylformamide), was synthesized via solvothermal reaction at 403 K for 24 h between adenine, zinc acetate dehydrate, and benzene tricarboxylic acid in DMF. The single-crystal structure of the framework was determined by single-crystal X-ray diffraction techniques in the monoclinic space group P2(1)/n and was refined to the final error indices R1/wR2 = 0.0663/0.1714 for I > 2sigma(I). The coordination of adenine and BTC expands the structure in different directions, resulting in a three dimensional structure. This framework contains a pore with the size ca. 6.6 × 3.9 A. The chemical stability, thermal stability, and cation-exchange characteristics were investigated by powder XRD, TGA, EDX, 1H NMR, and EA.

Work function based sensing of alkanes and alcohols with benzene tricarboxylate linked metal organic frameworks

Metalorganic frameworks (MOFs) are porous crystalline materials that can be synthesized using various metal ions and organic linkers. Due to their great physical, chemical, and geometrical variety, MOFs are very attractive for the potential application as selective gas sensing materials. The selectivity and sensitivity towards target gases is affected by chemical and/or geometrical properties of sensing layers. In this study we examine work function based gas sensing properties of MOFs, consisting of the same organic linker, benzene tricarboxylate (BTC), and different metal sites (Co, Ni, Cd, Al), towards different linear alkanes and monohydric alcohols at room temperature. The influence of oxygen and humidity on the gas sensing performances as well as the possible reaction mechanism are discussed. It was shown that exposure to alcohol leads to strong and concentration dependent changes in work function that increase with increasing length of the carbon chain of the alcohol while alkanes with similar carbon chains can hardly be detected. Moreover, the type of the metal site does not affect sensing of alcohols and alkanes qualitatively. By analysing the influence of size and polarity of the target gases, we assume that adsorption mechanisms and adsorption sites on BTC–MOF for polar and nonpolar molecules are different.

Competitive I2 Sorption by Cu-BTC from Humid Gas Streams

Competitive sorption of molecular iodine gas from a mixed stream containing iodine and water vapor is identified and characterized for the hydrophilic Cu-BTC metal–organic framework. By combining simulation (Grand Canonical Monte Carlo and molecular dynamics simulations) with crystallography (high-energy synchrotron-based powder X-ray diffraction data and pair distribution function analyses), we show that I2 substantially adsorbs, in preference to water vapor, into two principal areas. First, it adsorbs in the smallest cage close to the copper paddle wheel. Second, it adsorbs within the main pore with close interactions with the benzene tricarboxylate organic linker. Analysis suggests that I2 forms an effective hydrophobic barrier to minimize water sorption. The finding is relevant to mixed gas streams in nuclear energy industrial processes and accident remediation. This also represents the highest reported I2 sorption by a metal–organic framework (175 wt % I2 or 3 I/Cu).

SUMOF-5: a mesoporous metal-organic framework with the tbo topology built from the dicopper paddle-wheel cluster and a new tritopic linker

A mesoporous metal-organic framework Cu 3 (PTB) 2 (H 2 O) 3 · guest (denoted as SUMOF-5) has been synthesized using a new tritopic linker pyridine-2,4,6-tribenzoic acid (H 3 PTB). SUMOF-5 is cubic with the space group Fm-3m and a = 47.272(3) Å. The framework is built of the dicopper paddle-wheel secondary building unit (SBU) [Cu 2 (OOC) 4 (H 2 O) 2 ] and contains two different äcavities of 1.22 and 2.33 nm in diameter, respectively. The framework topology follows the (3,4)-connected tbo net, and can be regarded as an extended version of Cu 3 (BTC) 2 (H 2 O) 3 · guest (HKUST-1, BTC = benzene tricarboxylate). The structure of SUMOF-5 is compared to other MOFs built from dicopper paddle-wheels and tritopic linkers. SUMOF-5 has permanent porosity with a Langmuir surface area of 1733 m 2 /g and is stable in various organic solvents, which makes this material potentially useful as a crystalline carrier for loading molecular catalysts or drugs.

Metal–organic framework membranes with layered structure prepared within the porous support

A uniquely microstructured membrane, a metal–organic framework (MOF) layer within the porous support, was prepared by a counter-diffusion method. The MOF-based membrane prepared from the copper benzene tricarboxylate (Cu-BTC), one of the MOFs, exhibited excellent gas perm-separation properties with an ideal H2/CH4 selectivity of 153.

Copper Benzene Tricarboxylate Metal–Organic Framework with Wide Permanent Mesopores Stabilized by Keggin Polyoxometallate Ions

Porous solids with organized multiple porosity are of scientific and technological importance for broadening the application range from traditional areas of catalysis and adsorption/separation to drug release and biomedical imaging. Synthesis of crystalline porous materials offering a network of uniform micro- and mesopores remains a major scientific challenge. One strategy is based on variation of synthesis parameters of microporous networks, such as, for example, zeolites or metal-organic frameworks (MOFs). Here, we show the rational development of an hierarchical variant of the microporous cubic Cu(3)(BTC)(2) (BTC = 1,3,5-benzenetricarboxylate) HKUST-1 MOF having strictly repetitive 5 nm wide mesopores separated by uniform microporous walls in a single crystal structure. This new material coined COK-15 (COK = Centrum voor Oppervlaktechemie en Katalyse) was synthesized via a dual-templating approach. Stability was enhanced by Keggin type phosphotungstate (HPW) systematically occluded in the cavities constituting the walls between the mesopores.