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Crystalline porous materials are currently a hot research topic in the field of proton-conducting materials. Crystalline porous materials include metal–organic frameworks (MOFs), coordination polymers (CPs), polyoxometalates (POMs) and covalent organic frameworks (COFs). The designable structures and high surface areas of these materials provide great opportunities to orderly accommodate proton carriers and to systemically modify the concentration and mobility of proton carriers in available spaces. Based on the understanding of the relationship between the structure and proton conductivity, controllable synthesis of porous materials with high proton conductivity will gradually be achieved. This review summarizes the emerging studies of these materials and their unique proton conductivities. [ABSTRACT FROM AUTHOR]

Mercury(II) ions have emerged as a widespread environmental hazard in recent decades. Despite different kinds of detection methods reported to sense Hg2+, it still remains a challenging task to develop new sensing molecules to replenish the fluorescence-based apparatus for Hg2+ detection. This communication demonstrates a novel fluorescent sensor using UiO-66-NH2 and a T-rich FAM-labeled ssDNA as a hybrid system to detect Hg2+ sensitively and selectively. To the best of our knowledge, it has rarely been reported that a MOF is utilized as the biosensing platform for Hg2+ assay. [ABSTRACT FROM AUTHOR]

A new anionic framework {[Me2NH2]0.125[In0.125(H2L)0.25] ⋅ xDMF} n ( 1) with one-dimensional (1D) channels along the c axis of about 13.06×13.06 Å2, was solvothermally synthesized and well characterized. Post-synthetic cation exchange of 1 with Eu3+, Tb3+, Dy3+, Sm3+ afforded lanthanide(III)-loaded materials, Ln3+@ 1, with different luminescent behavior, indicating that compound 1 could be used as a potential luminescent probe toward different lanthanide(III) ions. Additionally, compound 1 exhibits selective adsorption ability toward cationic dyes. Moreover, the RhB@ 1 realized the probing of different organic solvent molecules by tuning the energy transfer efficiency between two different emissions, especially for sensing DMF. This work highlights the practical application of luminescent guest@MOFs as sensors, and it paves the way toward other one/multi-color luminescent host-guest systems by rational selection of MOF hosts and guest chromophores with suitable emissive colors and energy levels. [ABSTRACT FROM AUTHOR]

A series of lanthanide metal-organic frameworks (Ln-MOFs) are synthesized through solvothermal conditions with 1,3-bis(4-carboxyphenyl)imidazolium (H2L). Owing to the lanthanide contraction effect, two different types of Ln-MOFs, namely, {[Ln(L)2(OH)]·3H2O}n (Ln:Pr, Nd, Sm) and {[Ln(L)2(COO)(H2O)2]·H2O}n (Ln: Eu, Gd, Tb, Dy, Tm, Yb, Y), and their corresponding codoped Ln-MOFs Eu xTb1- xL are obtained. With careful adjustment of the relative concentration of the lanthanide ions and the excitation wavelength, the color of the luminescence can be systematically modulated and white light emission can be further successfully achieved. Furthermore, by virtue of the temperature-dependent luminescent behavior, Eu0.2Tb0.8L allows for the design of a thermometer with an excellent linear response to temperature over a wide range, from 40 to 300 K. This work highlights the practical applications of Ln-MOFs for tailoring fluorescent color and even obtaining practical white light emission, and especially for sensing temperature as luminescent thermometers in a single framework by controlling in different ways. [ABSTRACT FROM AUTHOR]

A sensor with a red-emission signal is successfully obtained by the solvothermal reaction of Eu3+ and heterofunctional ligand bpydbH2 (4,4′-(4,4′-bipyridine-2,6-diyl) dibenzoic acid), followed by terminal-ligand exchange in a single-crystal-to-single-crystal transformation. As a result of treatments both before and after the metal-organic framework formation, accessible Lewis-base sites and coordinated water molecules are successfully anchored onto the host material, and they act as signal transmission media for the recognition of analytes at the molecular level. This is the first reported sensor based on a metal-organic framework (MOF) with multi-responsive optical sensing properties. It is capable of sensing small organic molecules and inorganic ions, and unprecedentedly it can discriminate among the homologues and isomers of aliphatic alcohols as well as detect highly explosive 2,4,6-trinitrophenol (TNP) in water or in the vapor phase. This work highlights the practical application of luminescent MOFs as sensors, and it paves the way toward other multi-responsive sensors by demonstrating the incorporation of various functional groups into a single framework. [ABSTRACT FROM AUTHOR]

A tetranuclear copper cluster-based MOF with sulfonate–carboxylate ligands has been synthesized. It possesses one-dimensional irregular channels lined with sulfonate, carboxylate, and DMF molecules, which show a high proton conductivity of 7.4 × 10−4 S cm−1 at 95 °C and 95% relative humidity. [ABSTRACT FROM AUTHOR]

A new type of 3D lanthanide(iii) metal–organic framework directly constructed by double-chain motifs was synthesized. It shows a proton conductivity of 1.6 × 10−5 S cm−1 at 75 °C at 97% RH, and tunable emission including white light. [ABSTRACT FROM AUTHOR]

A red‐emitting Eu metal‐organic framework (EuMOF) is successfully obtained by S.‐Y. Song, H.‐J. Zhang, and co‐workers and serves as a multi‐responsive luminescent sensor toward different organic molecules and inorganic ions. On page 4034, the red emission signal is changed after exposing the EuMOF to the analytes under UV light excitation: some of them even quench the luminescence. This work paves the way for the practical application of luminescent MOF sensors for pollutant detection. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs), as novel developing porous crystalline materials, are promising candidates in the field of heterogeneous catalysis because of their high surface area, diverse structures, low densities, adjusted pore sizes, etc. Recently, increasing attention has focused on developing MOF-supported/derived materials as heterogeneous catalysts. In this review, we present the recent development of MOFs as supports or precursors in the preparation of various functional nanomaterials for heterogeneous catalytic reactions including electrocatalysis, organocatalysis, and photocatalysis. Here, we present a comprehensive discussion on the recent progress and the rational design of MOF-supported or derived heterogeneous catalysts to provide insights into the future development of novel and highly efficient heterogeneous catalysts. [ABSTRACT FROM AUTHOR]

Sixnovel complexes, namely, {[Zn1.5(L)(bix)1.5(H2O)]·H2O}n(1), {[Co1.5(L)(bix)1.5(H2O)]·H2O}n(2), {[Co3(L)2(4,4′-bpy)3]·5H2O}n(3), {[Cd3(L)2(4,4′-bpy)3]·4.5H2O}n(4), {[Cu3(L)2(4,4′-bpy)3]·3H2O}n(5), and {[Ni1.5(L)(4,4′-bpy)1.5(H2O)3]·2H2O}n(6)have been synthesized by the hydrothermal reaction of 5-(4-carboxy-2-nitrophenoxy)isophthalicacid (H3L) with different transition metal ions in thepresence of ancillary ligands, 1,4-bis(imidazol-1-ylmethyl)benzene(bix) and 4,4′-bipyridine (4,4′-bpy). Complexes 1and 2are isostructural, possessing a (3,8)-connected tfz-d type topology with the Schläfli symbol of {43}2{46·618·84}. The 3D structures of complexes 3–5are very similar to complex 1with only a littledifference of the H3L coordination motif in complexes 4and 5.Meanwhile, we use 4,4′-bpy insteadof bix as the ancillary ligand in all three complexes. Complex 6is a mixed one-dimensional chain and two-dimensional sheetstructure, which are further linked to each other in a three-dimensionalframework by H-bond interactions. All the complexes are characterizedby single crystal X-ray diffraction, IR spectroscopy, thermogravimetryanalysis, and elemental analysis. In addition, the luminescent propertiesof complexes 1and 4are discussed, andthe magnetic properties of complexes 2and 3are also investigated. [ABSTRACT FROM AUTHOR]