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Two novel complexes, {[Cd 3 (L) 2 (H 2 O) 2 ]·(H 2 O) 4 } n (1) and {[Mn(HL)(H 2 O) 2 ]·(H 2 O)} n (2), which are synthesized by the reaction of 3-(2, 4-dicarboxyphenyl)-4-carboxypyridine ligand with cadmium and manganese metal ions under the solvothermal method. The complex 1 is a 3D framework based upon trinuclear [Cd 3 (μ 2 -COO) 4 (μ 1 -COO) 4 (N) 2 ] SBUs, and the complex 2 is a one-dimensional metal oxygen chain based upon binuclear [Mn 2 (μ 2 -COO) 2 (μ 1 -COO) 2 (N) 2 ] SBUs. The solid fluorescence analysis of complex 1 reveals that the emission peak of 451 nm when its excitation peak is 336 nm. The fluorescence detection experiments of complex 1 showed that Fe3+, Cr 2 O 7 2− and CrO 4 2− can effectively to be detected. Furthermore, their limits of detection are 1.47 × 10−3 M, 1.31 × 10−3 M and 1.25 × 10−3 M, respectively. It has good recovery properties as a potential multifunctional fluorescence sensor. Besides, the quenching mechanism of fluorescence sensing is also discussed. In addition, the magnetic studies of complex 2 show strong antiferromagnetic interactions between its neighboring Mn(II) ions. [Display omitted] • Two novel stable complexes were constructed based on particular trinuclear and binuclear metal clusters. • Complex 1 shows high selectivity and sensitivity to detect Fe3+, Cr 2 O 7 2− and CrO 4 2− ions with low detection limit. • Complex 2 possesses antiferromagnetic interaction between its Mn (II) ions. [ABSTRACT FROM AUTHOR]

Two new 2D MOFs, namely, {[Cd 2 (HL)(H 2 O)(DMF) 2 ]·(H 2 O)·(DMF)} n (1), {[Co 2 (HL)(H 2 O)(DMF) 2 ]·(H 2 O)·(DMF)} n (2) were constructed under the solvothermal conditions by using 2,4-di(2′,5′-dicarboxylphenyl)benzoic acid and d10 metal ion Cd(Ⅱ) and Co(Ⅱ). Because the diversity of ligands leads to two different coordination patterns in complexes 1–2 , resulting in 1 and 2 with multiple structures. Both 1 and 2 exhibit a 3D supramolecular framework, which based on different metal-oxygen chains. The chains form a 2D layered structure through the carboxyl oxygen atoms in the ligand. The solid-state luminescence spectra of 1 at room temperature showed that the maximum emission peak is 458 nm (λex = 346 nm). At the same time, 1 showed high fluorescence selectivity and low detection limit for Fe3+ cations, Cr 2 O 7 2− and CrO 4 2− anions in aqueous solution, and can be used as a potential multifunctional material for the detection of these substances. In addition, the fluorescence sensing properties and quenching mechanism of the above ions are discussed in detail. [Display omitted] • Two novel 2D MOFs were constructed based on a V-shaped rigid pentacarboxylic acid ligand. • Complexes 1 and 2 feature 2D frameworks based on diverse metal-oxygen chains with high open metal sites. • 1 shows high selectivity and sensitivity to detect Fe3+, Cr 2 O 7 2− and CrO 4 2− ions with low detection limit. • The fluorescence quenching mechanism of complex 1 was described in detail. [ABSTRACT FROM AUTHOR]

Exploration of a highly effective, durable non-precious metal-based catalyst in oxygen evolution reaction remains a major challenge in the process of developing and utilizing hydrogen energy by electrocatalytic splitting water (OER). This study developed a simple and efficient method to synthesize CoFe-PBA by directly growing the Prussian blue analogues (PBAs) precursor on a self-supporting electrode with a conductive substrate, which is further phosphorized into CoFe–P/NF electrocatalyst. The high conductivity and large surface area of NF could accelerate electron transmission and increase the number of active sites. Fe incorporation could also enhance electronic structure and optimize adsorbate energy. The obtained CoFe–P/NF exhibits excellent electrocatalytic performance for the OER in 1 ​M KOH, which only provides overpotentials of 264 and 278 ​mV at current densities of 100 and 200 ​mA ​cm−2, respectively, and exhibits excellent durability over 120 ​h. This method provides a feasible strategy for exploring high-efficiency oxygen evolution reaction catalysts. The PBA precursor nanocubes of the CoFe-PBA/NF were subjected to low-temperature phosphating treatment to convert them into layered stacked nanosheets of the CoFe–P/NF, which have excellent activity and long-lasting stability for oxygen evolution reactions. [Display omitted] • PBA including multiple metals are a research hotspot for oxygen evolution catalysts. • Iron incorporation can optimize the electronic structure and reduce the adsorption energy for chemical reactions. • NF with 3D frameworks can enhance electron transport and prevent atomic agglomeration. • Cubic precursors are transformed into nanosheets scattered on NF after phosphating. • The catalyst provides overpotentials of 264 mV ​and exhibits excellent durability over 120 ​h. [ABSTRACT FROM AUTHOR]

A series of new 1D isomorphic lanthanide metal-organic frameworks (Ln-MOFs), {[Ln(L)(H 2 O) 5 ]·2H 2 O} n (1-Ln , Ln ​= ​Eu, Tb, Dy and Eu x Tb 1-x), were synthesized via a rigid bifunctional N,O-containing 2-(1 H -tetrazol-5-yl)terephthalic acid (H 2 L) and Ln(III) ions as raw materials. It is worth noting that different ratios of Eu(III) and Tb(III) can be combined into the same Ln-MOFs to generate a series of new differently doped 1-Eu x Tb 1-x MOFs. Under the same excitation wavelength, the double emission peaks of Eu(III) and Tb(III) are produced, and the emission color gradually changes between yellow-green, yellow, orange, and red. The sensing studies have shown that 1-Tb is an excellent reusable luminescence probe, suitable for simultaneous detection of dimetridazole (DMZ), metronidazole (MDZ) and tetracyclinehydrate (TET) in the aqueous solutions. Furthermore, magnetic measurements show that 1-Dy has slow magnetic relaxation properties. A series of new 1D isomorphic lanthanide metal-organic frameworks (Ln-MOFs), {[Ln(L)(H 2 O) 5 ]·2H 2 O} n (1-Ln , Ln ​= ​Eu, Tb, Dy and Eu x Tb 1-x), had been synthesized, and the 1-Eu x Tb 1−x doped MOFs achieve tunable emission from yellow-green to yellow to red. Besides, 1-Tb can be used to detect dimetridazole (DMZ), metronidazole (MDZ), and tetracycline (TET) in water and serum sensitively and selectively through fluorescence quenching, and 1-Dy has a slow magnetic relaxation performance. [Display omitted] • Series of isostructural Ln-MOFs had been synthesized by a rigid ligand. • A series of doped 1-Eu x Tb 1−x MOFs were obtained to achieve tunable emission. • 1-Tb has the high selectivity and sensitivity to detect DMZ, MDZ and TET. • 1-Dy has the slow magnetic relaxation properties. [ABSTRACT FROM AUTHOR]

In this paper, two unique 3D MOFs, namely, {[Cd 5 (L) 2 (H 2 O) 16 ]·4H 2 O} n (1), {[Pb 5 (L) 2 (H 2 O) 2 ]·6H 2 O} n (2) were obtained by taking advantage of 2,4-di(3′,5′-dicarboxylphenyl)benzoic acid (H 5 L) and Cd(Ⅱ), Pb(Ⅱ) metal ions under solvothermal conditions. The coordination diversity of the H 5 L ligand gives rise to two distinct coordination modes in 1 – 2 , which contributes to the MOFs with multifarious structures. Complex 1 exhibits a 3D 5-connected topology, and Cd(Ⅱ) metal ions of 1 show three different coordination geometries. 2 displays a 3D (2,3,4,7)-connected net on the basis of penta-nuclear [Pb 5 (μ 1 -COO) 5 (μ 2 -COO) 5 ] clusters, as well the structure of complex 2 contains specific 1D Pb– O –Pb chains. A room temperature, 1 – 2 shows eminent solid-state luminescence properties and the maximum emission peaks are ∼416 ​nm & ∼429 ​nm respectively. At the same time, due to the luminescence quenching effect of complex 1 , it reveals excellent selectivity and sensitivity for Fe3+ cations and Cr 2 O 7 2− anions with low detection limit. The fluorescence quenching mechanisms of complex 1 were also lucubrated. In this paper, two unique 3D MOFs, namely, {[Cd 5 (L) 2 (H 2 O) 16 ]·4H 2 O} n (1), {[Pb 5 (L) 2 (H 2 O) 2 ]·6H 2 O} n (2) were obtained by taking advantage of 2,4-di(3′,5′-dicarboxylphenyl)benzoic acid (H 5 L) and Cd(Ⅱ), Pb(Ⅱ) metal ions under solvothermal conditions. The coordination diversity of the H 5 L ligand gives rise to two distinct coordination modes in 1 – 2 , which contributes to the MOFs with multifarious structures. Complex 1 exhibits a 3D 5-connected topology, and Cd(Ⅱ) metal ions of 1 show three different coordination geometries. 2 displays a 3D (2,3,4,7)-connected net on the basis of penta-nuclear [Pb 5 (μ 1 -COO) 5 (μ 2 -COO) 5 ] clusters, as well the structure of complex 2 contains specific 1D Pb– O –Pb chains. A room temperature, 1 – 2 shows eminent solid-state luminescence properties and the maximum emission peaks are ∼416 ​nm & ∼429 ​nm respectively. At the same time, due to the luminescence quenching effect of complex 1 , it reveals excellent selectivity and sensitivity for Fe3+ cations and Cr 2 O 7 2− anions with low detection limit. The fluorescence quenching mechanisms of complex 1 were also lucubrated. [Display omitted] • Two novel 3D LMOFs were constructed based on a symmetrical V-shaped rigid pentacarboxylic acid ligand. • Complexes 1 and 2 feature 3D frameworks based on diverse metal chains and clusters with high open metal sites. • 1 – 2 shows eminent solid-state luminescence properties at room temperature. • Complex 1 has high selectivity and sensitivity to detect Fe3+ and Cr 2 O 7 2− ions with low detection limit. [ABSTRACT FROM AUTHOR]

Two new complexes {[Cd 3 L 2 (4,4'-bipy)(H 2 O) 2 ]·2H 2 O} n (1) and {[Zn 3 L 2 (4,4'-bipy)(H 2 O)]·H 2 O} n (2), were synthesized successfully based on 5-((carboxy-3-thio) methyl)isophthalic acid (H 3 L) and 4,4'-bipyridine (4,4'-bipy) auxiliary ligands under solvothermal conditions. Complexes 1 and 2 have the three-dimensional (3D) crystal structures, which contain infinitely extended one-dimensional (1D) metal chains decorated by open metal sites (OMSs). 1 and 2 both show good thermal stability and excellent water resistance. Fluorescence tests showed that complex 1 has high selectivity and sensitivity to detect Fe3+, Cr 2 O 7 2− and CrO 4 2− ions in aqueous solution. In addition, complex 1 is an excellent heterogeneous catalyst for the cycloaddition of CO 2 and epoxides that catalytic efficiency of epichlorohydrin is higher than 99% under mild conditions. Two new complexes {[Cd 3 L 2 (4,4'-bipy)(H 2 O) 2 ]·2H 2 O} n (1) and {[Zn 3 L 2 (4,4'-bipy) (H 2 O)]·H 2 O} n (2) were synthesized. 1 as a fluorescent probe can detect Fe3+, Cr 2 O 7 2− and CrO 4 2− ions in aqueous solution quickly and accurately with low detection limit especially. Meanwhile, complex 1 exhibits great catalytic performance for CO 2 and epoxides due to the abundant open metal sites (OMSs) embellished the 1D channel. [Display omitted] • Two new complexes were constructed based on 5-((carboxy-3-thio) methyl)isophthalic acid. • Complexes 1 and 2 feature 3D porous frameworks with high open metal sites. • Complex 1 has high selectivity and sensitivity to detect Fe3+, Cr 2 O 7 2− and CrO 4 2− ions. • The desolvated 1 exhibits great catalytic performance for CO 2 and epoxides under mild conditions. [ABSTRACT FROM AUTHOR]