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Fatigue vehicle load is essential for fatigue analysis, whose accuracy is directly associated with fatigue design. With the development of society, traditional fatigue vehicle load may fail to reflect modern traffic conditions, especially for transportation hubs in developed areas. Based on traffic flow data of a long-span steel box girder bridge, statistical analysis is performed and the two types of standard vehicle load are equivalent. Further, fatigue characteristics and fatigue life of two types of welded connection are compared based on the equivalent structural stress method. As a result, 2-axle vehicle takes the largest proportion, and the overload ratio of a 6-axle vehicle is the highest. Compared with fatigue vehicle load III, there should be a correction coefficient 1.89 and 2.30 for equivalent vehicle load based on average traffic flow and heavy lane traffic flow, respectively. For a single-side welded connection and a double-side welded connection, the equivalent structural stress will increase by 81.0%–131.2% for positions of concern when considering heavy lane traffic flow, which is about 21% higher than results considering average traffic flow. In addition, the fatigue life of these concerned positions will encounter a dramatic decrease. Fatigue life of the most unfavorable position is 492.4 years and cracks will occur in 90.0 years based on fatigue vehicle load III. However, it will decrease to 42.3 years and 7.7 years, respectively, when considering the traffic flow of the heavy lane. [ABSTRACT FROM AUTHOR]

The fatigue cracks of rib-to-deck welded joints in an orthotropic steel deck are one of the critical conundrums that restrict the sustainable development of steel bridges. Double-sided welded joints were achieved by introducing internal welding technology to overcome the initial "crack-like" manufacturing defects at the welding roots of single-sided welded joints. Through the observation of the macro-section of the welded joint, the differences between single-sided welding, partial-penetration welding, and full-penetration welding in rib-to-deck welded joints are compared. Relying on the Shenzhen–Zhongshan link, the fatigue failure and mechanism of single-sided rib-to-deck welded joints are clarified by the nominal stress and structural stress methods, and those of double-sided welded joints were determined through fatigue tests. The fatigue strength of rib-to-deck welded joints is higher than the FAT90 of Chinese standard and the FAT C joints of American standard. The fatigue strength of double-sided rib-to-deck welded joints is significantly higher than that of single-sided welded joints. The fatigue strength of rib-to-deck welded joints is within a ± 2σ range of main S-N curves by the structural stress method. It is suggested to adopt the double-sided welded joints in practice, and to ensure that the penetration rate is beyond 80%. The trial data are limited, and further tests are needed to confirm the results. [ABSTRACT FROM AUTHOR]

Development of luminescent coordination polymers (LCPs) for effective detection of the environmental pollutants is urgent and important for human health and environmental protection. Three novel Zn-LCPs, {[Zn1(L)(4,4′-bbibp)]–[Zn2(L)(4,4′-bbibp)]}n [YMUN6 (for Youjiang Medical University for Nationalities)], [Zn(L)(1,4-bimb)]n (YMUN7), and [Zn(L)(4,4′-bidpe)]n (YMUN8), were fabricated from flexible dicarboxylic acid 1,3-bis(4′-carboxylphenoxy)benzene (H2L) and different imidazole ligands [4,4′-bbibp = 4,4′-bis(benzimidazol-1-yl)biphenyl, 1,4-bimb = 1,4-bis(imidazol-1ylmethyl)benzene, 4,4′-bidpe = 4,4′-bis(imidazolyl)diphenyl ether] using solvothermal conditions. They were characterized using X-ray diffraction (XRD), infrared (IR), thermogravimetric (TG), powder X-ray diffraction (PXRD), and photoluminescence (PL) spectroscopic techniques. YMUN6 possessed the "ABAB" interpenetrating 2D complanate structure. YMUN7 showed a three-interpenetrating 2D network. YMUN8 displayed a hcb 3-connected 3-fold interpenetrated 2D network. Photoluminescent properties of YMUN6–8 were investigated, and 6–8 served as "turn off" sensors that could detect chlortetracycline (Chl), Ag+, and Cr2O72− in an aqueous solution with simultaneous high efficiency and sensitivity. Notably, the investigation of Ag+ sensing was most focused on lanthanide metal LCPs, and Zn-LCPs have rarely been reported in this direction. Furthermore, selectivity and recyclability were also investigated. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have a good designability, a well-defined pore, stimulus responsiveness, a high surface area, and a controllable morphology. Up to now, various MOFs have been widely used as nanocarriers and have attracted lots of attention in the field of drug delivery and release because of their good biocompatibility and high-drug-loading capacity. Herein, we provide a comprehensive summary of MOF-based nanocarriers for drug delivery and release over the last five years. Meanwhile, some representative examples are highlighted in detail according to four categories, including the University of Oslo MOFs, Fe-MOFs, cyclodextrin MOFs, and other MOFs. Moreover, the opportunities and challenges of MOF-based smart delivery vehicles are discussed. We hope that this review will be helpful for researchers to understand the recent developments and challenges of MOF-based drug-delivery systems. [ABSTRACT FROM AUTHOR]

An easy prepared probe, BHMMP, was designed and synthesized, which displayed a significant fluorescence enhancement (over 38-fold) and obvious color change in the recognition of Al3+. The binding ratio of probe BHMMP to Al3+ was determined as 1:1, according to Job plot. The binding mechanism was fully clarified by the experiments, such as FT-IR spectrum, ESI–MS analysis, and 1H NMR titration. A DFT study further confirmed the binding mode of BHMMP to Al3+. The limit of detection (LOD) for Al3+ was determined as low as 0.70 µM, based on the fluorescence titration of BHMMP. Moreover, the results from real sample experiments, including real water samples, test papers, and cell images, well-demonstrated that BHMMP was capable of sensing Al3+ in environmental and biological systems. [ABSTRACT FROM AUTHOR]

Recently, lots of organic dye adsorbents were introduced; the pollution of water bodies caused by adsorbents was an urgent problem to be solved. The modified metal–organic frameworks with magnetic properties provided a great platform for solving this disadvantage. In this study, a novel magnetic material Fe3O4@PmPD–[Co-BT] (Co-BT = [Co(bcpo)0.5(tib)(H2O)2]n, bcpo = 2,5-bis(4-carboxylphenyl)-1,3,4-oxadiazole, tib = 1,3,5-tris(1-imidazolyl)benzene)) was prepared using Fe3O4 modified by mPDs (mPD = m-phenylenediamine). This material was successfully characterized by transmission electron microscopy (TEM) and powder X-ray diffraction (PXRD), and it was confirmed that Co-BT was adhered to the Fe3O4 surface by PmPDs. The dye adsorption performance of magnetic Fe3O4@PmPD–[Co-BT] was investigated in detail with selectivity, capacity, thermodynamics and kinetics studies, and with respect to influence factors including the pH value, solvent types, and ionic strength. Notably, the saturated adsorption capacity of magnetic Fe3O4@PmPD–[Co-BT] for CR dyes could reach 347.8 mg g−1. The dye removal mechanism was investigated by zeta potential analyses and Fourier transform infrared (FTIR) spectroscopy. [ABSTRACT FROM AUTHOR]

Two novel Co (II)‐ coordination polymers (CPs) based on 2,5‐bis(4‐carboxylpheny)‐1,3,4‐oxadiazole (bcpo), namely [Co/(bcpo)0.5(tib)(H2O)2]n (1) and [Co (bcpo)0.5(bidpe)(H2O)2]n (2) (tib = 1,3,5‐tirs(1‐imidazolyl)benzene, bidpe = 4,4′‐bis (imidazolyl)diphenyl ether) have been synthesized under solvothermal conditions and characterized by powder X‐ray diffraction (PXRD), single crystal X‐ray diffraction, photochemistry as well as electrochemistry. The investigation of the photo‐degradation methyl blue and methyl violet (MB, MV) properties of CPs 1–2 demonstrates that CP 1 shows great performance for the degradation of MB, and CP 2 could efficiently degrade MB/MV. Meanwhile, the possible photo‐degradation mechanism has been proposed and explored. Simultaneously, electrochemistry studies show that both CPs 1 and 2 can catalyze water oxidation under an alkaline condition at the potential around 1.20 V vs. NHE with relatively low overpotential of 330–510 mV vs. NHE. [ABSTRACT FROM AUTHOR]

Mg batteries are attractive for low-cost and sustainable energy storage because Mg as an anode material is highly abundant in the crust of the Earth, it has a high charge capacity (2205 Ah kg−1 or 3832 A h L−1) benefiting from its two electron redox chemistry, and it undergoes less dendritic growth than other metals (Li and Na). However, the development of Mg batteries is still hampered by the lack of easy-to-make, chemically stable Mg electrolytes. In the current work, we conveniently prepared an ionic liquid Mg electrolyte (MMAC-IL) by mixing MgCl2, AlCl3, Mg, and 1-butyl-1-methylpyrrolidinium bis(trifluoromethanesulfonyl)imide (Pyr14TFSI) together and using them in a one-pot reaction; the product of this reaction did not need to be purified. The MMAC-IL electrolyte exhibited superior anodic and cathodic electrochemical performances, according to electrochemical and spectroscopic studies. Specifically, MMAC-IL delivered robust Mg deposition/stripping cycling for 300 h with minimum polarization change in Mg/Mg half-cell studies. Moreover, the MMAC-IL electrolyte with its high ionic strength significantly suppressed the shuttle effect of magnesium polysulfides and enabled a stable Mg–S battery. [ABSTRACT FROM AUTHOR]

A novel metal organic framework, namely, {[Zn3(btc)2(bimmb)2.5]·2H2O·CH3CN}n (1) (btc = 1,3,5-benzenetricarboxylic acid), bimmb = 1,4-bis(imidazol-l-ylmethyl) benzene), has been reasonably designed, successfully solvothermally synthesized, and characterized. The complex is characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, thermogravimetric analysis, and powder X-ray diffraction. Complex 1 exhibits a 5-nodal 3,3,4,4,6-connected 3D framework with a (5·6·7)2(52·8)2(52·92·102)2(53·82·9)2(54·62·72·84·92·11) topology. The photodegradation studies reveal that complex 1 displays highly sensitive photodegradation sensing toward methylene blue, rhodamine B, and methyl violet under UV irradiation. [ABSTRACT FROM AUTHOR]

Two novel 3D functional CPs based on the flexible 4-(4-carboxylphenylmethylthio)benzoic acid ligand have been successively synthesized. Complex 2 that is composed of Co(II), 4,4′-H 2 cpmb and 1,3-Hbib ligand displays good photo-degradation and adsorption properties for the organic dyes. Two new coordination polymers (CPs) based on transition metals, namely [Ni 2 (4,4′-cpmb) 2 (4,4′-bbibp) 2 (H 2 O) 4 ] n (1) and [Co(4,4′-Hcpmb)(1,3-bib)] n (2) (flexible 4,4′-H 2 cpmb = 4-(4-carboxylphenylmethylthio)benzoic acid, rigid 4,4′-bbibp = 4,4′-bis(benzoimidazo-1-ly)biphenyl and 1,3-Hbib = 1,3-bis(1-imidazo-1-ly)benzoic acid), have been designed and successfully synthesized under solvothermal conditions, which have been characterized by elemental analysis, infrared spectra, thermogravimetric (TG) analysis, powder X-ray diffraction (PXRD) and single-crystal X-ray diffraction. Single-crystal X-ray diffraction analysis reveals that 1 features a 3D supermolecular structure in ABAB mode by H bonds (O⋯H⋯O) with a 2-fold interpenetrating sql topology framework and 2 displays a 3D supermolecular framework by H bonds (O⋯H⋯O) with a rarely fes topology. Moreover, the photo-degradation and dye adsorption properties of CPs 1 – 2 have been investigated. Importantly, 2 shows good photo-degradation and dye adsorption properties. [ABSTRACT FROM AUTHOR]

Five novel Cd(II) metal–organic frameworks (Cd-MOFs), namely [Cd6(L)4(1,3-bit)2(H2O)4]n (1), [Cd(HL)(4,4′-bbibp)]n (2), [Cd3(L)2(1,4-bimb)2(H2O)2]n (3), [Cd(HL)(4,4′-bidpe)]n (4) and [Cd3(L)2(1,1′-bbi)(H2O)4]n (5) (flexible H3L = 5-(2-carboxylphenoxy)isophthalic acid, rigid 1,3-bit = 1,3-bis(l-imidazoly)toluene, rigid 4,4′-bbibp = 4,4′-bis(benzoimidazo-1-ly)biphenyl, semi-flexible 1,4-bimb = 1,4-bis(imidazol-l-ylmethyl)benzene, semi-flexible 4,4′-bidpe = 4,4′-bis(imidazolyl)diphenyl ether, and flexible 1,1′-bbi = 1,1′-(1,4-butanediyl)bis(imidazole)) were synthesized employing a rational design approach under solvothermal conditions and further characterized by elemental analysis, IR spectra, thermogravimetric (TG) analysis, powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction. Diversity architectural topologies have been generated by adjusting the N-donor ligands. They exhibit varied structures: 1 displays an unprecedented 6-nodal (3,3,4,4,8,8)-c 3D topology framework with the point Schläfli symbol of (3·4·5)2(32·42·52·66·78·87·9)(32·63·7)(4·64·8)(410·611·87)(43)2; 2 shows a 2-fold interpenetrating 4-connected cds topology with the point Schläfli symbol of (65·8); 3 exhibits an unprecedented 2-nodal (3,8)-c 3D topology network with the point Schläfli symbol of (42·5)2(44·56·610·75·82·9); 4 shows a 4-connected sql topology with the point Schläfli symbol of (44·62); 5 displays a tfz-d topology 2-nodal (3,8)-c 3D network with the point Schläfli symbol of (43)2(46·618·84). The luminescence studies reveal that MOFs 1–5 display highly sensitive and selective fluorescence sensing towards Fe3+ cations, CrO42− anions and molecular acetone. Meanwhile, the targeted dye adsorption properties of MOFs 1–5 are investigated. [ABSTRACT FROM AUTHOR]

Four novel Zn(ii) metal–organic frameworks (MOFs) including {[Zn(L)0.5(bimb)]·2H2O·0.5(CH3)2NH}n (1), {[Zn(L)0.5(bimmb)]·2H2O}n (2), {[Zn(L)0.5(btdpe)]·H2O}n (3), and [Zn(L)0.5(bidpe)]n (4) (H4L = 5,5′-(1,4-xylylenediamino) diisophthalic acid, bimb = 1,4-bis(imidazol-1-yl)-butane, bimmb = 1,4-bis(imidazol-1-ylmethyl)benzene, btdpe = 4,4′-bis(4H-1,2,4-triazol-4-yl)diphenyl ether, and bidpe = 4,4′-bis(imidazolyl)diphenyl ether) were solvothermally prepared and further characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, thermogravimetric (TG) analysis and powder X-ray diffraction (PXRD). Single-crystal X-ray diffraction analysis showed that complex 1 features a 3-fold interpenetrated bbf topological framework with the Schläfli symbol of (64·82)(66)2. Complex 2 displayed an unprecedented 2-nodal (4,4)-connected 3D framework with the Schläfli symbol of (86), while complexes 3 and 4 showed 3-nodal (2,4,4)-connected (4·8·104)2(4)2(84·10·12)-unprecedented frameworks. Luminescence studies revealed that complexes 1–4 can be used as high selectivity luminescence sensors for sensing Fe(iii) cations, Cr(vi) anions (Cr2O72− and CrO42−) and nitroaromatic compounds. Furthermore, a possible sensing mechanism was investigated in this paper. [ABSTRACT FROM AUTHOR]

Three novel coordination polymers (CPs) based on transition metals, namely {[Cu(bpt)2(H2O)2]·2NO3}n (1), {[Cu(bpt)(SO4)(H2O)]·H2O}n (2) and [Cd(bpt)(SO4)]n (3) (tib = 1,3,5-tris(1-imidazolyl)benzene and bpt = 2,5-bis(4-pyridyl)-1,3,4-thiadiazole), have been designed and successfully synthesized under solvothermal conditions. All of these three polymers were characterized by single crystal X-ray diffraction, elemental analysis, IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). Single-crystal X-ray diffraction analysis reveals that complex 1 possesses a uninodal 4-connected 3D (three-dimensional) spl topology framework with the point symbol (44·62). Complex 2 showing a 1D zigzag chain, which is connected by a sulfate anion to form a 2D network, is further assembled into a 3D supramolecular structure, whereas complex 3 displays a 3D 3,5-connected tfz-d topology with chiral inorganic 2-D layers. Moreover, the photocatalytic degradation of the three complexes has been investigated. Significantly, complex 1 is the best photocatalyst for the degradation of organic dyes (MB/MV/RhB). [ABSTRACT FROM AUTHOR]

Graphical abstract Two 3D functional coordination polymers based on the rigid 1,3,5-tris(1-imidazolyl)benzene ligand and cobalt transition metal have been successively synthesized. Complex 2 shows good photo-catalysis properties for the photo-catalytic degradation of mixed organic dyes (MB/MV/RhB). Abstract Two novel coordination polymers (CPs) based on cobalt transition metal, namely {[Co(tib) 2 ]·2HNO 3 } n (1) and {[Co(tib)(4,4′-sbdc)]·H 2 O} n (2) (tib = 1,3,5-tris(1-imidazolyl)benzene, H 2 sbdc = 4,4′-stilbenedicarboxylic), have been designed and successfully synthesized under solvothermal conditions, which were characterized by elemental analysis, infrared spectra, powder X-ray diffraction (PXRD), thermogravimetric (TG) analysis and single-crystal X-ray diffraction. Single-crystal X-ray diffraction analysis reveals that complex 1 features a stable 2D → 3D supramolecular frameworks through H-bonds with a rare (3,6)-connected kgd topology and complex 2 displays a 2-fold interpenetrating (2,4)-connected new topology with the point Schläfli of (44·62)(42). Importantly, the photo-catalytic properties of complexes 1 – 2 have been investigated, and then complex 2 is a good photo-catalyst for the degradation of mixed organic dyes (MB/MV/RhB). [ABSTRACT FROM AUTHOR]

Four novel Co(ii) metal–organic frameworks, namely [Co2(4,4′-cpmb)2(1,1′-bbi)2]n (1), [Co(4,4′-cpmb)(4,4′-bbibp)]n (2), {[Co(4,4′-cpmb)(tib)]·3(H2O)}n (3) and {[Co(4,4′-sdc)(tib)]·(H2O)}n (4) (flexible 4,4′-cpmb = 4-(4-carboxylphenylmethylthio)benzoic acid, rigid 4,4′-sdc = 4,4′-stilbenedicarboxylic acid, flexible 1,1′-bbi = 1,1′-(1,4-butanediyl)bis(imidazole), rigid 4,4′-bbibp = 4,4′-bis(benzoimidazo-1-ly)biphenyl and rigid tib = 1,3,5-tris(1-imidazolyl)benzene) were synthesized employing a rational design approach under solvothermal conditions and further characterized by elemental analysis, IR spectra, thermogravimetric (TG) analysis, powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction. The four Co-MOFs display different interpenetrated structures due to the flexibility of O/N-donor ligands. Single-crystal X-ray diffraction analysis reveals that complex 1 displays a 6-fold interpenetrating class Ia net with the point Schläfli symbol of (66). Complex 2 shows a 3-fold interpenetrating sqc5 net with the point Schläfli symbol of (66·8). Complexes 3 and 4 exhibit a 2-fold interpenetrating 4-connected sql topology with the point Schläfli symbol of (44·62). The photodegradation properties and dye adsorption capacity of complexes 1–4 are investigated, and the framework integrity of complexes 1–4 can be well-retained. [ABSTRACT FROM AUTHOR]

Two novel luminescent coordination polymers, namely, {[Zn(tmlb)(H2tmlb)]·H2O}n (1) and [Zn(tmlb)(bbibp)]n (2) ((bbibp = bis(benzoimidazo-1-ly)biphenyl), H2tmlb = (1H-1,2,4-triazol-1-yl)methylenebis(benzoic acid)), have been rationally designed and successfully solvothermally synthesized. Complexes 1 and 2 have been characterized by elemental analysis, IR spectroscopy, single-crystal X-ray diffraction, thermogravimetric (TG) analysis and powder X-ray diffraction (PXRD). Complex 1 possesses a 2-fold interpenetrating 3-connected 3D framework with a point symbol of (63) topology. Complex 2 exhibits a two-fold interpenetrating uninodal 4-connected 3D framework with a (65·8) topology. The luminescence studies reveal that complexes 1 and 2 display highly sensitive and selective luminescent sensing towards Cr(vi) (CrO42− and Cr2O72−) anions, and complex 2 displays highly sensitive and selective luminescence sensing towards Fe(iii) cations. In addition, photocatalytic studies show that complex 1 could be a good candidate for the photocatalytic degradation of methylene blue (MB), and complex 2 could be a good candidate for the photocatalytic degradation of methylene violet (MV) and Rhodamine B (RhB). [ABSTRACT FROM AUTHOR]

• Two novel Zn (II) coordination polymers have been successfully prepared and characterized. • An unprecedented topology with 4-nodal 3, 3, 5, 6-c framework. • Chem-sensors with excellent performance for the detection of Fe3+ ions or TC, high selectivity, extra sensitivity. Environmental issues are the great challenge that human beings are suffering from. Development in coordination polymers (CPs) provides a great platform for tracing hazardous substance by fluorescence detection. In this work, two novel Zn-CPs, namely [Zn(1,1′-bbi)(C 2 O 4)] n (1) and [Zn 3 (1,1′-bbi)(L) 2 (H 2 O)] n (2) (flexible 1,1′-bbi = 1,1′-(1,4-butanediyl)bis(imidazole), and H 3 L = 5-(2-carboxylphenoxy)isophthalic acid) have been synthesized under solvothermal conditions, and further characterized by IR spectra, elemental analyses, thermogravimetric (TG) analyses, powder X-ray diffraction (PXRD), and single-crystal X-ray diffraction. Complex 1 displays a sql topological framework; complex 2 shows an unprecedented 4-nodal (3,3,5,6)-c topological network with Point Schläfli symbol (4·5·6) 2 (42·52·62·73·9) 2 (42·52·64·7·84·9·10)(42·5) 2. CPs 1 – 2 possess good application prospect due to their high thermal, and chemical stability. The selective and sensitive fluorescence sensing of 1 – 2 have been investigated towards Fe3+ ions and tetracycline in detail. [ABSTRACT FROM AUTHOR]

Three novel Cu (II) coordination complexes, formulated as [Cu3(C14H8NO3F)2(CH3COO)2]n (1), [Cu2(C14H9NO3F)2(CH3COO)Cl] (2) and [Cu(C14H8NO3F)(CH3OH)2] (3), have been synthesized by 3‐Fluoroanthranilic acid, Salicylaldehyde and Cu (II) salt as sources in different reaction conditions and characterized by single crystal X‐ray diffraction, X‐ray powder diffraction, IR spectroscopy and elemental analysis. Single‐crystal diffraction analysis revealed that the complexes exhibited different coordination modes and conformations which were linked into multidimensional networks through some weak interactions. The biological activities vary greatly on account of the different Cu (II) numbers among the three complexes. In order to discuss the bioactivities, the complexes have been screened for antimicrobial activities against E. coli and S. aureus, antitumor activities against A549 (human lung cancer cells), Hela (human cervical cancer cells) and HepG‐2(human liver hepatocellular carcinoma cells). Their interactions with calf thymus DNA were investigated by UV–visible and fluorescence spectrometry, as well as viscosity measurements. Interestingly, 1 (the rare 3‐core Cu (II) coordination polymer) shows great antibacterial activities and highest DNA binding affinities. Antitumor studies revealed that complex 1 also exhibited highest activity. [ABSTRACT FROM AUTHOR]

One novel metal–organic frameworks (MOFs) has been successfully synthesized under solvothermal condition and characterized by single crystal X-ray diffraction. The electrochemical behaviors of the complex have been studied in 0.1M KOH. Photocatalytic properties have been confired by degrading rhodamine B (RhB), methylene violet (MV), and methylene blue (MB). Possible degradation mechanism and the effect of the variables have been discussed. One novel metal–organic frameworks (MOFs) constructed by one angular ligand and 5-aminoisophthalic acid, namely {[Ni(L)(bpt)(H 2 O)]·2H 2 O} n (H 2 L = 5-aminoisophthalic acid, bpt = 2,5-bis(4-pyridyl)-1,3,4-thiadiazole) has been designed and successfully synthesized under solvothermal condition. This compound was characterized by single crystal X-ray diffraction, elemental analysis, IR spectra, powder X-ray diffraction (PXRD), and thermogravimetric analysis (TGA). Single-crystal X-ray diffraction analysis reveals that the compound possesses a uninodal 3-connected 3D (three-dimensional) hcb topology framework with the point symbol (63). The thermal stabilities and electrochemical behavior in the solid state of the compound have been investigated in detail. Moreover, the photocatalytic degradation of the compound has been investigated. The results show photocatalytic activity of the compound for three dyes is MB > MV > RhB. [ABSTRACT FROM AUTHOR]

The as-synthesized PCN-222(Fe) nanosheet can efficiently immobilize aptamers to fabricate an electrochemical aptasensor, which is used as an efficient platform for impedimetric sensing toward tobramycin. [Display omitted] • A PCN-222(Fe) nanosheet is prepared successfully. • It can efficiently immobilize aptamers to fabricate an electrochemical aptasensor. • It is used as an efficiently impedimetric sensor toward tobramycin. A zirconium metal-organic framework nanosheet, namely PCN-222(Fe) NS, is prepared using [5,10,15,20-tetrakis(4-carboxyphenyl)porphyrinato]-Fe(III) chloride and Zr clusters, which is further investigated in detail by various technologies. The as-synthesized PCN-222(Fe) NS can efficiently immobilize aptamers to construct an electrochemical aptasensor for impedimetric sensing toward tobramycin (TOB). The fabricated electrochemical aptasensor can sensitively monitor TOB with outstanding specificity, fine long-term preservation, acceptable repeatability as well as good actual usability. [ABSTRACT FROM AUTHOR]

Two novel Ni(II) CPs have been successfully synthesized, which could be good candidates for the photocatalytic degradation of organic dyes. • Synthesis of two different Ni(II) coordination polymers by introduction of carboxylic acid ligands. • Frame structure and photodegradation properties of the two complexes have been discussed. • The possible mechanism of photocatalytic degradation of dyes is explored. Two different novel coordination polymers were synthesized under hydrothermal conditions, namely {[Ni(bibp) 3 (H 2 O) 2 ]·2NO 3 ·0.5H 2 O} n (1), [NiL(bibp)] n (2) (H 2 L = 3,3′-azodibenzoic acid, bibp = 4,4′-bis(imidazolyl)biphenyl). Complex 2 is based on the introduction of carboxylic acid ligands on complex 1. These two polymers were characterized by single crystal X-ray diffraction, IR spectra, elemental analysis, powder X-ray diffraction (PXRD), and thermogravimetric (TG) analysis. Single crystal X-ray diffraction analysis showed that complex 1 formed a 3D structure by weak force. Complex 2 possesses a uninodal 4-connected 3D (three-dimensional) sql topology framework with the point symbol (44·62). In addition, the photocatalytic degradation properties of the two complexes are investigated. Significantly, complex 1 is a good photocatalyst for the degradation of organic dyes (RhB/MO), complex 2 is a good photocatalyst for the degradation of organic dyes (MB). And the possible photodegradation mechanism was proposed and explored. [ABSTRACT FROM AUTHOR]

[Display omitted] • Produce novel Co-based MOFs that possess analogous layered stacked structure. • Require only 1.2 V@2.93 mA cm−2 and 1.5 V@2.78 mA cm−2 for full water splitting. • Exhibit efficient photocatalytic degradation abilities towards MB/MV in aqueous solution. Two novel Co-MOFs constructed from aromatic polycarboxylic acid named {[Co(tib) 2 (bimb) 2 ]·4H 2 O} n (tib = 3-((4-(1H-1,2,4-triazol-1-yl)benzyl)oxy)benzoic acid, bimb = 1,4-bis(imidazole-1-ylmethy) benzene) and {[Co 2 (bipa) 4 (bibp) 6 ]} n (bipa = 2-(4-carboxy-2-nitrophenoxy)-6-nitroterephthalic acid, bibp = 4,4′-bis(imidazolyl) biphenyl), have been synthesized under solvothermal conditions and characterized by single-crystal X-ray diffraction, elemental analysis, IR spectra, powder X-ray diffraction (PXRD), thermogravimetric analysis (TG) as well as electrochemistry. The single-crystal X-ray diffraction analysis indicates that Co-MOF 1 exhibits an uninodal net with a (65·8) topology, whereas Co-MOF 2 exhibits an uninodal 4-connected framework with a (44·62) topology. The electrochemistry studies demonstrate that both of the two Co-MOFs can behave as the efficient electrocatalysts for water oxidation in a mild neutral system at the potential around 1.20 V vs. NHE with comparatively low overpotential (η) for Co-MOF 1 and 2 of 337–541 mV vs. NHE. Moreover, the two Co-MOFs also show good photocatalytic degradation capabilities toward MB/MV dyes under UV irradiation, and the mechanism studies demonstrate that the main active species are · OH radicals. Therefore, these bi-functional Co-MOFs materials can be treated as convenient and efficient catalysts for the oxygen evolution reaction and aromatic dyes degradation. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are increasingly becoming an important choice for developing robust and efficient electrocatalysts; therefore, exploring the relationship between the structure, catalytic activity, and stability of MOFs is of great significance. MOFs 1 - 3 with different spatial configurations are designed and synthesized based on linear pyridine ligands, tetragonal carboxylic acid ligands, and triangular carboxylic acid ligands, while MOF 4 displays a three-dimensional (3D) supramolecule assembled through a mixed-ligand strategy. Compared with MOFs 1 - 3 , MOF 4 has the lowest overpotential of 106 mV (at 10 mA·cm -2 ) and a Tafel slope of 80.9 mV·dec -1 , as well as sturdy long-term stability in the process of oxygen evolution reaction (OER). The presence of dense metal clusters and μ 3 -O promotes the optimal catalytic performance of MOF 4 . Density functional theory (DFT) calculations of MOF 4 demonstrate that the process from O* to OOH* is the rate-determining step. This investigation further reveals the relationship between MOF structural composition and electrocatalytic OER performance and provides an effective strategy for the assembly of MOF-based electrocatalysts.