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A stable porous sorbent M1 was achieved through the specific transformation of flexible thioalkyl groups and metal cluster sites in a zirconium MOF (metal–organic framework; Zr-L) template. The target polymer combines sulfoxide/sulfone and phosphoric acid in a single framework, which was fully characterized by 1H-NMR, PXRD, IR, and elemental analysis. When employed as the heavy metal adsorbent, M1 exhibit a remarkable Eu­(III) sorption behavior, achieving both high chemical affinity (Kd = 105) and sorption capacity (the maximum Eu­(III) sorption capacity reached 220 mg g–1 at pH = 4.0 and T = 298 K calculated from the Langmuir model). Recyclability and selectivity test of M1 further prove that the sorbent is highly stable and effective for europium enrichment in the aqueous solution. This work takes focus on the introduction of multifunctional groups into a single polymeric framework in a feasible and environmentally friendly way and highlights the sorption efficiency for europium removal from the aqueous solution.

Organic-inorganic ABX3 (A, B = cations, X = anion) hybrids with perovskite structure have recently attracted tremendous interest due to their structural tunability and rich functional properties, such as ferroelectricity. However, ABX3 hybrid ferroelectrics with other structures have rarely been reported. Here, we successfully designed an ABX3 hybrid ferroelectric [(CH3)3NCH2F]ZnCl3 with a spontaneous polarization of 4.8 μC/cm2 by the molecular modification of [(CH3)4N]ZnCl3 through hydrogen/halogen substitution. It is the first zinc halide ABX3 ferroelectric, which contains one-dimensional [ZnCl3]-n chains of corner-sharing ZnCl4 tetrahedra, distinct from the anionic framework of corner-sharing or face-sharing BX6 octahedra in the ABX3 perovskites. From zero dimension to one dimension, the high symmetry of ZnCl4 tetrahedra is broken, and all of them align along one direction to form a polar [ZnCl3]-n chain, beneficial to the generation of ferroelectricity. This finding provides an efficient polar anionic framework for enriching the family of hybrid ferroelectrics by assembling with various cations and should inspire further exploration of new classes of organic-inorganic ABX3 ferroelectrics.

Crystalline coordination architectures with coordinatively unsaturated metal sites are of great importance for their attractive properties. Tunable side chains of the 4-formylimidazole here were employed for directing the subcomponent self-assembly of (CuIIN4)2(CuII)2 (1), {(CuIIN4)(CuII)2}n (2), {L(CuII)2}n (3) under the same solvothermal condition, giving the structural diversity. The unique square-planar CuII/NiIIN4 units with open metal sites can not only be in situ embedded in 1 and 2, but also be successfully immobilized in {(NiIIN4)2(CuICN)9}n (4) and {(CuIIN4)2(CuICN)9}n (5), through the metalloligand strategy. Enzyme-like substrate-specific activity was observed by employing 5 as a heterogeneous catalyst, which exhibit increased activity and high selectivity towards the catalytic oxidation of 1-phenylethyl alcohol derivatives. This work presents two promising methodologies for the introduction of controllable open metal sites in versatile crystalline coordination complexes and their application i...

Over the last few years, numerous efforts have been made to develop white light emitting metal–organic frameworks (MOFs), due to the useful features of MOFs such as ultrahigh surface areas and tunable pore architecture. However, rare earth (RE) ions are most commonly applied as phosphors in these materials so far, raising device cost and environmental concerns. Here, we designed a new type of RE-free material capable of white light emission upon excitation at 365 nm, with the photoluminescence quantum yield in the solid state reaching 37%, fabricated by compositing carbon dots (CDs) with a Zr(IV)-based MOF. WLEDs constructed by depositing the CDs/Zr-MOF nanocomposite on a commercial UV LED chip feature CIE chromaticity coordinates of (0.31, 0.34), a high color rendering index (CRI) of 82, and a luminous efficiency of 1.7 lm W−1.

Like killing two birds with one stone, we here utilize sulfur functionalization to simultaneously mitigate the persistent instability issue of the famous Zr(IV)-based metal–organic frameworks (MOFs) and impart effective metal uptake capabilities for broader potential applications. Thioether side groups can be conveniently designed to have various sizes and configurations, and offer unique advantages for functionalizing and stabilizing highly porous frameworks. Sulfuration as such on Zr(IV)-based frameworks is meaningful, because these MOF materials, in spite of their improved stability when protected by solvents, often degrade fast upon exposure to air, therefore limiting applications that involve gas–solid interfaces. For better practical impact, here we install sulfur side chains, e.g., tris(methylthiomethyl)methyl, that are conveniently derived from inexpensive pentaerythrityl compounds. One notable advance achieved pertains to a UiO-68-type porous solid (i.e., based on terphenyl dicarboxyl linkers) featuring long-term stability in direct exposure to air, while maintaining significant mercury uptake capability from water and organic solutions. Also discovered is a cubic NU-1100-type net that offers more efficient mercury removal capability (with regards to the adsorption capacity as well as binding strength as measured from the distribution coefficient Kd) than other thioether-equipped MOF materials.

Here, the sulfur-functionalized zirconium(IV)-based metal-organic frameworks (Zr-MOFs) with high luminous efficiency as a novel luminophore was used to construct the electrochemiluminescence (ECL) sensor. Compared to the ligand with the aggregate state as the luminophore, the Zr-MOFs with porous structure could relieve the ECL aggregation-caused quenching (ACQ) effect, resulting in an enhancement of ECL intensity. Impressively, the coreactant tripropylamine came from tripropylamine-modified gold nanoparticles (TPrA@AuNPs) were immobilized on Zr-MOFs to form the composite (TPrA@AuNPs/Zr-MOFs), which could significantly increase the local concentration of the coreactant on the surface of electrode, shorten the electron transport distance between the coreactant and the luminophore, reduce the energy loss during the reaction and further improve the ECL efficiency of the Zr-MOFs/TPrA ECL system. Finally, epinephrine (EP) was selected as model target molecule, the developed biosensor exhibited the linear range from 1.0 × 10−8 to 1.0 × 10−2 mol L−1 with a detection limit of 3.3 × 10−9 mol L−1 (S / N = 3) for EP. This strategy offered a method to improve the ECL efficiency of luminophore for the construction of efficient sensors to detect micromolecule.

With methylthio groups flanking the carboxyl groups, the 3,3′,5,5′-tetrakis(methylthio)biphenyl dicarboxylate (TMBPD) linker forms a zirconium(IV) carboxylate porous framework featuring the topology of the UiO-67 prototype, i.e., with a face-centered-cubic array of the Zr6O4(OH)4 clusters. Thioether functionalization proves valuable because the ZrTMBPD crystal is found to be exceptionally stable not only upon long-term exposure to air but also in boiling water and a broad range of pH conditions. The hydrophobicity of the metal–organic framework can also be tuned by simple H2O2 oxidation, as illustrated in the water contact-angle measurement of the pristine and H2O2-treated ZrTMBPD solid.

We employ a two-step strategy for accessing crystalline porous covalent networks of highly conjugated π-electron systems. For this, we first assembled a crystalline metal-organic framework (MOF) precursor based on Zr(IV) ions and a linear dicarboxyl linker molecule featuring backfolded, highly unsaturated alkyne backbones; massive thermocyclization of the organic linkers was then triggered to install highly conjugated, fused-aromatic bridges throughout the MOF scaffold while preserving the crystalline order. The formation of cyclized carbon links not only greatly strengthen the precursor coordination scaffold, but more importantly, enhance electroactivity and charge transport throughout the polycyclic aromatic grid.

Three copper(i)-metallosalen coordination polymers (CPs), {[Ni(II)(SalImCy)]2(Cu(I)CN)9}n (1), {[Cu(II)(SalImCy)]2(Cu(I)CN)9}n (2) and {[Ni(II)(SalImCy)](Cu(I)I)2·DMF}n (3) were prepared by direct combination of Ni(II)/Cu(II)(salen) motifs with [Cu(I)CN]n chains and Cu2I2 clusters via the metalloligand strategy. The mixed-valence and mixed-metal CPs could effectively catalyze both the oxidation of aromatic alcohols to ketones and aldehydes under mild conditions and photocatalytic degradation of organic dye methylene blue (MB). This work demonstrates the effective integration of transition metal catalytic Ni(II)/Cu(II)(salen) units and photoactive copper(i) species in a single solid polymer to meet the demand for catalytic materials with the dual catalytic properties.

A copper(i)/copper(ii)–salen coordination polymer prepared by solvothermal reactions shows prominent bimetallic catalytic activities towards three-component Strecker reactions and photodegradation of organic dyes under visible-light illumination.

Four new hemiterpenoid derivatives, taxilluside A-D (1-4), were isolated from the branches and leaves of Taxillus chinensis (DC.) Danser. Their structures were determined on the basis of spectroscopic analysis. Of these compounds, compounds 3 and 4 showed inhibition activity on Calcium concentration in myocardial cells evaluated by measuring the changes of fluorescence signal using Laser scanning confocal microscope.