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1, 4, 5, 8‐naphthalene diimide (NDI)‐based MOFs, due to their tunable structures and properties, have shown promising applications in photochromism, photocatalysis, electrocatalysis, photothermal therapy, etc. Herein, using an L‐alanine modified NDI ligand, i.e. N, N′‐bis(L‐alanine)naphthalenediimide (AlaNDI), a novel Cd‐NDI Cd (AlaNDI)(H2O)]·DMF·H2O (complex 1) was constructed under solvothermal conditions, which has an obvious different structure with the previously reported ones. Structural analysis shows that the packing structure of complex 1 consists of two adjacent Cd atoms sharing two AlaNDI ligands, forming a dimetallic building block [Cd2O8]. Each building block connects a total of four AlaNDI ligands, where two Cd atoms are bridged by two ligands. The building blocks are interconnected by ligands to form a two‐dimensional layered structure. Based on the features of the NDI skeleton, it was found that complex 1 possesses multiple stimulus responses involving sensitivity to light: a reversible photochromism property and good photocatalytic degradation activity against various dyes, especially against cationic dyes crystal violet (CV), methyl violet (MV), and Janus green B (JGB). In addition, the stimulus‐response mechanism was investigated by control experiments. It is revealed that the photocatalytic active species may be related to h+ and •OH. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The development of host‐guest MOF luminescent composites has attracted considerable attention. However, it is still a challenge to reasonably design large scale conjugated polycarboxylic acids metal‐organic framework (MOF) and modulate donor‐acceptor interaction. Herein, a series of isostructural 3D porous lanthanide MOF [Ln2(BINDI)0.5(NO3)(DMA)(H2O)]∙DMA∙2.5H2O (Ln = La (1), Ce (2), Pr (3) and Nd (4); H4BINDI (N,N'‐bis(5‐isophthalic acid)‐1,4,5,8‐naphthalenediimide) were synthesized. Considering the electron‐deficient performances of Ln‐BINDI MOFs, D‐A type composites Ln‐MOFs (1—4@H4TBAPy) were prepared via the incorporation of electron‐rich H4TBAPy (1,3,6,8‐tetrakis(p‐benzoic acid) pyrene), which more improved the luminescence performance of complexes 1—4 and can be used as fluorescence sensors for the detection of nitro compounds and aldehydes. High sensitivity of 1@H4TBAPy towards pNBA, pNA PNP, DNP, and TNP could be achieved through hydrogen bond interactions between MOF and analytes, as well as the π‐π interaction between H4TBAPy and the naphthalene ring of BINDI, thus the fluorescence quenching efficiency of 1@H4TBAPy was better than that of the complex 1. In addition, it is found that 1@H4TBAPy has high selectivity and sensitivity to aromatic aldehyde SA, 5‐Mesal and HMBA. Such strategy to enhance the emission of NDI based Ln‐BINDI MOFs, will open up an avenue to obtain more fluorescent MOFs for sensing. [ABSTRACT FROM AUTHOR]

Triazole polycarboxylic acid ligands are widely employed in the construction of MOFs due to their strong coordination ability and flexible coordination modes. In this work, three novel complexes (Pb(MCTCA)(H2O) (1), Co(HMCTCA)2(H2O)2 (2) and Cu(HMCTCA)2(H2O)2 (3)) based on the H2MCTCA ligand (5-methyl-1-(4-carboxyl)-1H-1,2,3-triazole-4-carboxylic acid) were successfully synthesized under hydrothermal conditions, respectively. X-ray single crystal structure analysis shows that complex 1 is a 3D network structure, where the central metal Pb(II) is six coordinated to form deformed triangular prism geometry. The complexes 2 and 3 are both 2D layer supramolecular structures connected through intermolecular hydrogen, where the central metals (Co/Cu) are six coordinated to form octahedral configuration geometry. Based on functional properties, it is found that complex 1 exhibits excellent detection ability for small-molecule drugs (azithromycin, colchicine and balsalazide disodium) and actinide cations (Th4+ and UO22+) within a lower concentration range without interference from other components. In particular, the detection limits of three small-molecule drugs are all lower than 0.30 μM. In addition, complexes 2 and 3 exhibited excellent catalytic reduction performance toward p-nitrophenol (PNP), with a reduction efficiency exceeding 98%. These experimental results evidence that complexes 1–3 have potential application prospects in fluorescence sensing and catalytic reduction. [ABSTRACT FROM AUTHOR]

Investigating the correlation between structural diversity and functionality serves as a pivotal factor in propelling the progress of functional materials, which however commonly needs tedious synthesis or sophisticated screening of conditions. Herein, we establish a facile strategy to synthesize two series of coordination networks (CNs, i.e., Ln-CMNDI and LN-CMNDI-F) with two distinct topologies using a solvent-directed method employing a specific ligand N,N′-bis(carboxymethyl)-1,4,5,8-naphthalenediimide (H2CMNDI) and rare-earth metal ions. The single-crystal X-ray diffraction analysis shows that Ln-CMNDI-F (Ln = La, Pr, Sm, Tb, Dy, Eu, Yb) synthesized using DMF and H2O as the solvents adopt a two-dimensional planar structure, while Ln-CMNDI (Ln= Ho, Gd, Tb, Yb, La and Eu) with three-dimensional supramolecular structures are obtained under the same conditions due to the existence of hydrogen bonding between molecules when DMF is replaced with DMA. The topology type of Ln-CMNDI-F is assigned as lcf (abbreviation of Ln-CMNDI-F) and the topological type of Ln-CMNDI is assigned as lcn (abbreviation of Ln-CMNDI) which are both not collected in the RCSR. Moreover, such differences in the changes of the topological structures lead to different optical properties including photochromism properties and fluorescence sensing abilities. The photochromism property of Ln-CMNDI-F is superior to that of Ln-CMNDI in terms of the speed of photoresponse. However, Ln-CMNDI exhibits a better performance in fluorescence sensing towards nitrophenols. This work reveals that Ln-CMNDI and Ln-CMNDI-F with novel topological structures can be constructed by adjusting the solvent reasonably, providing insights for the construction of CNs with promising optical applications. [ABSTRACT FROM AUTHOR]

A novel uranyl organic framework (U-hdpcp) based on flexible cyclic triphosphazene polycarboxylate ligands was prepared, which possesses the ability to sense aromatic aldehyde solutions (benzaldehyde, salicylaldehyde and 2-bromobenzaldehyde) and nitro compounds (2,4,6-trinitrophenol, 2,4-dinitrophenol and o-nitrophenol). A fluorescent thin film based on U-hdpcp@PVA with the ability to sense aldehyde vapors was prepared via a spin coating method. The work expands the library of UOF materials based on large-sized carboxylic acid ligands and demonstrates promising applications in the field of fluorescent sensors. [ABSTRACT FROM AUTHOR]

A new compound [Co2(H2BATD)(DMF)2]·2.5DMF·0.5H2O (1) was synthesized from the triazine ligand H6BATD (H6BATD = 5,5′-(6-biscarboxymethylamino-1,3,5-triazine-2,4-diyl) bis (azadiyl), DMF = N,N-dimethylformamide) and Co(NO3)2·6H2O. Compound 1 was characterized using infrared spectroscopy, UV-vis spectroscopy, PXRD, and thermogravimetry. The three-dimensional network of compound 1 was further constructed using [Co2(COO)6] building blocks from the flexible coordination arms and the rigid coordination arms from the ligand. In terms of functional properties, compound 1 can be used for the catalytic reduction of p-nitrophenol (PNP) to p-aminophenol (PAP), and compound 1 with a dose of 1 mg showed good catalytic reduction properties, as well as a conversion rate of over 90%. Based on the unique π-electron wall and carboxyl groups in the H6BATD ligand that provide abundant adsorption sites, compound 1 can be used to adsorb iodine in cyclohexane solution. [ABSTRACT FROM AUTHOR]

Nowadays, selective removal of cationic or anionic organic dyes from aqueous solution has become a new research focus. Meanwhile, metal–organic framework materials have attracted extensive attention in the field of wastewater treatment due to their porous structures. From this perspective, based on pyridine–imidazole heterocyclic ligand 2,4,5-tri(4-pyridine)-1H-imidazole (Htpim), two new complexes Ni(Htpim)2Cl2·2H2O (1) and Co(Htpim)2(OH)Cl·7H2O (2) were firstly designed and synthesized by the solvothermal method under 100 °C condition. Meanwhile, complexes 1 and 2 were characterized by various microanalyses. Also, the crystal structures of complexes 1 and 2 were determined by single-crystal X-ray diffraction. The results indicated that the three-dimensional supramolecular structures of both complexes 1 and 2 were connected by π–π interactions. To explore their functional properties, the adsorption capacities of complexes 1 and 2 for organic dyes were investigated in water. The experimental results exhibited that complexes 1 and 2 had better selective adsorption toward eosin dye with negative charges. According to the Langmuir, Freundlich and Temkin isotherm models, it was found that the Langmuir isotherm was more consistent with the adsorption process of complexes 1 and 2, and the adsorption capacities of complexes 1 and 2 for eosin were 125 mg g−1 and 71.43 mg g−1, respectively. According to thermodynamic analysis, the adsorption process of complexes 1 and 2 was spontaneous. Meanwhile, it was found that the pH of the dye solution also had an influence on the adsorption process. Also, adsorption kinetic curve fitting showed that complexes 1 and 2 both conformed to pseudo-second-order curves. In addition, the possible adsorption mechanisms were explored. [ABSTRACT FROM AUTHOR]

Viologens (1,1'‐disubstituted 4,4'‐bipyridyls) possessing electron‐deficient properties and redox activity are a class of suitable chromophores to assemble metal–organic hybrid photochromic materials. Thus, viologen‐functionalized metal–organic frameworks (MOFs) have attracted much attention for their photochromic properties; however, the syntheses of lanthanide‐viologen hybrid crystalline photochromic materials still face many challenges. For example, the structures and properties of the final products are difficult to predict and are limited by molecular configurations. In this work, host‐guest composite‐material Ln‐NH2BDC‐pbpy MOFs were constructed by encapsulating viologen derivative pbpyCl2. The pbpy2+ moieties are uniformly embed by their π‐π conjugation in the pores of the 3D structure by electrostatic interactions. Due to the encapsulation of the chromophore pbpy2+ moieties, Ln‐NH2BDC‐pbpy MOFs have reversible photochromic properties: they can change color after irradiation and can return to the original color after being protected from light or heating. Interestingly, the fluorescence intensity decreases with illumination time and recovers in the dark. As a result, Ln‐NH2BDC‐pbpy MOFs show both photochromic and photomodulated fluorescence. Based on the outstanding fluorescence performance of the Ln‐NH2BDC‐pbpy MOFs, they also show a wonderful effect for detecting nitrophenols, especially TNP. [ABSTRACT FROM AUTHOR]

Two naphthalene diimide-based (NDI-based) complexes, [Cd(AlaNDI)(NH2-BDC)0.5(H2O)]·(CH3)2NH2 (1) and [Cd(AlaNDI)(BDC)0.5(H2O)]·(CH3)2NH2·(CH3)2NH (2) (AlaNDI = N,N′-bis(L -alanine)naphthalenediimide, H2BDC = terephthalic acid, NH2–H2BDC = 2-amino terephthalic acid), were successfully prepared under solvothermal conditions. The complexes were characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis (TG), X-ray powder diffraction (PXRD), and UV-vis absorption spectroscopy techniques. Structural analysis showed that the packing structures of the complexes were assembled with the subunit Cd2(AlaNDI)2 connected by BDC or NH2-BDC moiety, forming an interspersed two-dimensional structure. In order to investigate the effect of uncoordinated amino groups in the complexes, structural comparisons and functional properties of iodine adsorption, photochromism, and photocatalysis were explored. Photocatalytic studies showed that both the complexes have good potential for photocatalytic degradation activity of various dyes, particularly for cationic dye crystal violet (CV), basic saffron (SFT), malachite green (MG), and methyl violet (MV). We found that the photocatalytic active species may be related to h+ and ˙OH. [ABSTRACT FROM AUTHOR]

A novel Co-MOF (Co-tcbpe) based on the TPE derivative H4tcbpe (H4tcbpe = 4′,4′′′,4′′′′′,4′′′′′′′-(ethene-1,1,2,2-tetrayl)tetrakis([1,1′-biphenyl]-4-carboxylic acid)) was designed and synthesized under solvothermal conditions. It was found experimentally that Co-tcbpe is a kind of MOF material that undergoes reversible color changes in response to various stimuli (solvent and temperature conditions). For example, Co-tcbpe can show different colors in different solvents, and its color can return to its original color when it is removed from the solvent. By analyzing the FT-IR, UV-vis, and fluorescence spectra and fluorescence lifetime of the sample after solvent treatment, combined with the analysis of the 3D stacking structure of Co-tcbpe, it is speculated that the reason for solvatochromism is the hydrogen bonding interaction between the solvent molecules and the coordinated water molecules in the Co-tcbpe structure. Furthermore, Co-tcbpe also exhibited superior thermochromic phenomena (pink-dark green-yellow) under different temperature conditions. In the same way, in order to find out the reason for the thermochromism of Co-tcbpe, we also carried out its structural characterization, combined with the DSC curve and TGA analysis, and proved that the cause of thermochromism may be the desolvation process. These obvious color changes that can be observed with the naked eye also make Co-tcbpe become a new type of sensor that could respond to small organic molecules and temperature, which also provides a solid foundation for us to further study and develop the application field of MOFs based on TPE derivatives. [ABSTRACT FROM AUTHOR]

Thorium‐based metal–organic frameworks (MOFs) are unique, which are substantially less reported compared to the MOFs based on transition metal and rare earth elements. Here, a thorium‐MOF (Th‐TCBPE) based on 4',4'',4''',4''''‐(ethene‐1,1,2,2‐tetrayl)tetrakis([1,1'‐biphenyl]‐4‐carboxylic acid) (H4TCBPE) and thorium nitrate is synthesized first. Th‐TCBPE is an interpenetrated 2D network, where Th (IV) is ten‐coordinated with a bicapped dodecahedron coordination geometry. Further studies about the structure by time‐resolved emission spectra (TRES) analysis are also discussed. What's more, Th‐TCBPE has excellent thermal stability and good tunable AIE property on concentration in THF. The photophysical properties of Th‐TCBPE in different solvents, different concentrations in THF, and different ratios of THF/H2O are studied. The ability of Th‐TCBPE to detect nitro aromatic compounds is also investigated. It is also believed that this work can provide theoretical guidance and inspiration for the development of Th‐MOF and MOF with AIEgens in the future. [ABSTRACT FROM AUTHOR]

Retraction of 'Multifunctional luminescence sensing and white light adjustment of lanthanide metal–organic frameworks constructed from the flexible cyclotriphosphazene-derived hexacarboxylic acid ligand' by Meng Wang et al., Dalton Trans., 2021, 50, 14618–14628, https://doi.org/10.1039/D1DT02560K. [ABSTRACT FROM AUTHOR]

A new compound {[Zn7(DPOT)2(H2O)11]·2OH·3H2O·5DMA} (1) was synthesized by the reaction of the H6DPOT ligand (H6DPOT= 5,5′,5′′-((1, 3, 5-triazine-2,4,6-triyl)tris(oxy)) tri-isophthalic acid, DMA= N,N-dimethylacetamide) and Zn(NO3)2·6H2O using a solvothermal method. It was characterized by elemental analysis, infrared spectroscopy, ultraviolet spectroscopy, thermogravimetric analysis and X-ray powder diffraction. The crystal structure of 1 was determined by X-ray crystallography diffraction. The three-dimensional cage structure is formed by [Zn2(COO)4(H2O)2] and [Zn2(COO)3(H2O)4] building blocks. By exploring fluorescence sensing on nitro aromatic compounds (NACs) and hydroquinone (HQ), the results show that 1 has a smart fluorescence sensing ability for NACs and HQ. For HQ, the Ksv was 2.9 × 104 M−1, and the limit of detection (LOD) value was 9.5 μM. For 2,4,6-trinitrophenol (TNP), the Ksv was 2.4 × 105 M−1, and the LOD value was 1.12 μM. [ABSTRACT FROM AUTHOR]

The development of fluorescent heterocyclic compounds bearing s-triazine and cyclotriphosphazene scaffolds for researching the structure–property relationship and high-efficiency amine sensing is still challenging. Herein, we prepared two polypodal aldehyde-based flexible organic compounds based on triazine and cyclotriphosphazene units (TRIPOD and HAPCP). Moreover, two hydrogen-bonded organic frameworks, namely HOF-TRIPOD and HOF-HAPCP, with different photophysical properties and structural packing modes were obtained. In addition, the fluorescence response of the two molecules to aliphatic amine was studied, in which they all showed good selectivity and an obvious fluorescence enhancement effect to ethylenediamine. The utilization of these fluorescent molecules as a sensor platform material could be applied for ethylenediamine detection. [ABSTRACT FROM AUTHOR]

Luminescent metal organic frameworks (LMOFs) are considered to be a type of promising optical sensing material due to their designable and tunable functions, and stable pore structures. Therefore, the preparation of LMOFs has become a research hotspot in recent years. As we know, triazine carboxylic acid ligands are conducive for constructing LMOF materials due to their large π electron conjugated system. In this work, two crystalline materials [Cd3(TCPT)2]·0.5DMF·4H2O (1) and (H3O)[Zn2(TCPT)(μ2-OH)2]·0.5DMF·3H2O (2) were obtained by the reaction of the triazine carboxylic acid ligand 2,4,6-tris(4-carboxyphenoxy)-1,3,5-triazine (H3TCPT), as an extended carboxylate arm, and d10 transition metal salts. Their structures were determined by single crystal X-ray diffraction and characterized by infrared spectroscopy (IR), ultraviolet visible spectroscopy (UV-vis), fluorescence spectroscopy, powder X-ray diffraction (PXRD) and thermogravimetric analysis (TG). The experimental results showed that complexes 1 and 2 show excellent fluorescent emission behavior. Thus, we explored their fluorescence sensing properties. To our delight, the results showed that they both had the ability to sense small organic drug molecules and aromatic amine molecules containing o-phenylenediamine (OPD), m-phenylenediamine (MPD) and p-phenylenediamine (PPD). In general, the practical applications of a MOF material are usually limited because of the relatively harsh synthesis methods. In this aspect, we studied the synthesis method in detail to obtain the optimal reaction conditions for the large-scale synthesis of 1 and 2. The preparation of the two LMOF materials only required about 3 hours of heating time and they could be prepared on a large scale, which is significant for the practical applications of LMOFs. [ABSTRACT FROM AUTHOR]

Two silver cluster compounds {[Co(1,10′-phen)3]2‧[Ag8I12]} (1) and {[Co(2, 2′-bipy)3]‧[Ag10I11]‧(OH)‧3DMF‧2H2O} (2) (1,10′-phen = 1,10′-phenanthroline, 2, 2′-bipy = 2,2′-bipyridine) were designed and synthesized by solvent evaporation method. The two silver cluster compounds were characterized by elemental analysis, infrared spectroscopy, ultraviolet spectroscopy, thermogravimetric analysis and X-ray powder diffraction. The crystal structures of compounds 1 and 2 were determined by X-ray crystallography diffraction. Through the electrostatic interaction between the metallic Ag cluster moiety and the metallic Co cluster moiety, form stable interlaced layered super molecular structures. In order to explore functional properties, the catalytic reduction of p-nitrophenol (PNP) and electrochemical behavior of compounds 1 and 2 were explored. The results show that compounds 1 and 2 can efficiently catalyze the reduction of PNP in the aqueous solution, and the reduction and removal rate can reach more than 90%. [ABSTRACT FROM AUTHOR]

The controllable design, synthesis and functional properties of a series of triazine tetratopic carboxylic MOFs have always been hotspots and challenges for research. Based on the characterization of the C–Cl bond on the triazine skeleton being easily substituted by some functional groups, we designed and synthesized a series of triazine tetratopic carboxylic Cu(II) and Zn(II) MOFs via the reaction of Cu(NO3)2·2.5H2O and ZnSO4·7H2O, as well as triazine tetratopic carboxylic H4TDBA-Cl (H4TBDA-Cl = 5,5′-((6-chloro-1,3,5-triazine-2,4-diyl)bis(azanediyl))diisophthalic acid) under hydrothermal conditions. During the process of synthesizing, the C–Cl bond on the triazine skeleton of the ligand was substituted with different groups, which formed the complexes ([Cu2(TBDA-Cl)(H2O)·10DMF·30H2O]n) (DMF = N,N-dimethylformamide) (1), N(Me)2 -[(CH3)2NH2]4·[Zn3(HTBDA-N)2(SO4)2]n (2) and H ([Cu2(TBDA-H)(H2O)]n) (3), respectively. It is worth noting that the in situ substitution reaction occurred for complexes 2 and 3 during the process of synthesis. Also, the structural analysis showed that the molecules in complexes 1–3 were connected with different building blocks to form different three-dimensional structures. We performed iodine adsorption experiments on the three complexes and found that there was a significant relationship between the structural configuration and adsorption behaviour. The results showed that the complex 1 with the Cl atom on the triazine skeleton could have a boosting effect on adsorption with iodine. It displayed a remarkable adsorption effect for iodine (in the solution of water: 7.6 g g−1 and in the solution of cyclohexane: 548.2 mg g−1). In addition, it also displayed the adsorption effect for JGB dye (204.9 mg g−1). For complex 2, it displayed an uptake effect for iodine in the solution of cyclohexane (529 mg g−1). The possible adsorption mechanism was also investigated. By comparison, we found that chlorine atoms could play an important role in the adsorption processes. The adsorption capacity of complex 1 (containing the chlorine atom in the structure) was much higher than that for complex 3. [ABSTRACT FROM AUTHOR]

The complex [Cd(PDNDI)]·DMF (Cd‐PDNDI) (H2PDNDI = N‐(4‐pyridine)‐4,5‐dicarboxy‐1,8‐naphthalene dicarboxyimide) was synthesized by the reaction of N,N′‐di(4‐pyridyl)‐1,4,5,8‐naphthalene diimide (DPNDI) and Cd(NO3)2·4H2O. It was characterized by elemental analysis, infrared spectroscopy, ultraviolet–visible (UV‐vis) spectroscopy, powder X‐ray diffraction (PXRD), single crystal X‐ray diffraction, and thermogravimetric analysis. Structural analysis shows that the Cd‐PDNDI has a self‐assembled 3D network structure with the rtl type topology. It is worth mentioning that the composition of the ligand is different from the initial raw material used in this molecular structure. This may be because the ligand undergoes an in situ hydrolysis reaction in the reaction system and becomes an NDI carboxylic acid derivative, which continues to join coordination reaction with the metal ion. In addition, the Cd‐PDNDI has an excellent photocatalytic effect on malachite green (MG) among the six dyes, which shows that the Cd‐PDNDI could be used as a photocatalytic material for the degradation of dyes. Highlights: A 3D complex Cd‐PDNDI was synthesized.The Cd‐PDNDI show higher degradation efficiency for MG and can be used as a potential photocatalyst.The possible mechanism of in‐situ reaction of ligands in Cd‐PDNDI is proposed, which provides a reference for the further development of NDI series complexes. [ABSTRACT FROM AUTHOR]

In this work, based on the conjugated structure of the naphthalene ring system, four stable Cd‐NDI complexes {[Cd(NDI−A)0.5(H2O)(o‐BDC)]⋅H2O}n (1); {[Cd(NDI−A)(DMF)(m‐BDC)]⋅H2O}n (2); {[Cd(NDI−A)(HCOO)(p‐BDC)0.5]}n (3); {[Cd1.5(NDI−A)2(H2O)2(TIBTC)] ⋅ 2H2O}n (4) (NDI‐A=N,N'‐di(4‐pyridylacylamino)‐1,4,5,8‐naphthalenediimide; o‐H2BDC=phthalic acid; m‐H2BDC=iso‐phthalic acid; p‐H2BDC=p‐phthalic acid; H3TIBTC=2,4,6‐triiodo‐1,3,5‐benzene tricarboxylic acid) are designed and synthesized. The four Cd‐NDI complexes have good luminescence properties, and complexes 1–3 can selectively detect Cr2O72− and L‐Arginine in water. Complex 1 has the best ability to detect Cr2O72− with a limit of detection (LOD) of 2.32 μM; complex 3 can be employed for the detection of L‐arginine with a LOD of 2.25 μM. Complex 1–3 may be useful for monitoring water quality and treating wastewater as a good fluorescence sensor. In addition, based on the specific detection species of C=N bonds by complexes 1–3, we take complex 3 as an example to conduct preliminary studies monitoring a Schiff base reaction in situ with fluorescence quenching. This provides a new method for monitoring organic reactions. Besides, we also have explored the ability of complex 4 to detect p‐nitroaniline. The results show that the complex 4 could selectively detect p‐nitroaniline with a LOD of 5.12 μM. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks [Co(Hbidc)(H2O)2] (1) and [Mn(Hbidc)(H2O)] (2), with multidentate 1H-benzimidazole-5,6-dicarboxylic acid (H3bidc) ligand, have been synthesized under hydro/solvothermal conditions and structurally characterized by elemental analysis, IR spectrum, and single-crystal X-ray diffraction. Single-crystal X-ray diffraction analysis revealed that the center Co atom of complex 1 is six-coordinated with three-dimensional supramolecular structure and center Mn of complex 2 is five-coordinated with exhibiting a 2D layered network. The photodegradation of Crystal violet dye and Methylene blue dye were studied firstly by complexes 1 and 2 as photocatalysts. Research result indicates that the degradation rate for complex 1 can reach 89.85% , 90.6% and that for complex 2 can reach 88.28% , 79.48%. At the same time, corresponding to photocatalytic kinetics was performed. [ABSTRACT FROM AUTHOR]

Two poly-iodine aromatic tricarboxylate complexes: {(Me2NH2)[Mn(TIBTC)(2, 2'-bipy)(H2O)]}n (1) and {(Me2NH2)[Co(TIBTC)(DMA)]}n (2) (DMA = N, N-dimethylacetamide), were designed and synthesized by the hydrothermal synthetic methods (TIBTC = 2, 4, 6-triiodo-1, 3, 5-benzenetricarboxylic acid). Complexes were characterized by microanalysis. The crystal structures of complexes 1 and 2 were determined by X-ray single-crystal diffraction. Complex 1 is a 3D network supramolecular network structure connected by the hydrogen bonds, and complex 2 is a 3D network structure. To explore their functional properties, we first investigated the adsorption capacity of complexes 1 and 2 for iodine capture in cyclohexane solution. The maximum adsorption capacity of complex 2 is 125 mg/g. Meanwhile, the adsorption kinetic curves fitting showed that complexes 1 and 2 all conformed to the pseudo-second-order curves. [ABSTRACT FROM AUTHOR]

Considering that cyclotriphosphazene polycarboxylic acid is a kind of organic ligand with fantastic structures and performances and the unique luminescence characteristics of rare earth ions, a series of porous lanthanide metal–organic frameworks (Ln-MOFs) (CH3)2NH2[Ln3(HCPCP)1.5(CH3COO)]·6DMA (Ln = Ce (1), Sm (2), Eu (3), Tb (4), HCPCP = hexa(4-carboxyphenoxy)cyclotriphosphazene, and DMA = N,N-dimethylacetamide) were synthesized with novel topological network structures. Compound 4 exhibited a sensitive recognition of –NO2, and had a fluorescence quenching phenomenon for seven kinds of nitro aromatic compounds (NACs). In particular, it showed the best fluorescence response to 2,4,6-trinitrophenol (TNP) and 2,4-dinitrophenol (DNP), and the KSV values were 2.86 × 105 M−1 and 8.21 × 104 M−1, and the limit of detection (LOD) values were 0.20 μM and 0.71 μM, respectively. At the same time, we successfully doped different concentrations of Eu3+ into compound 4 to obtain a series of doped Ln-MOF materials x%Eu3+@4 (x = 0.5, 2.5, 5, 7.5, 10, 15 and 20). With the increase of Eu3+ doping ratios, the characteristic peaks of Tb3+ and Eu3+ changed regularly, and the energy transfer from Tb3+ to Eu3+ ions occurred. By changing the excitation wavelength of the samples with different Eu3+ doping concentrations, a higher quality white light emitting material 7.5%Eu3+@4 (λex = 340 nm) was finally obtained, with a CIE coordinate of (0.3268, 0.3212). [ABSTRACT FROM AUTHOR]

Naphthalenediimide (NDI) derivatives have attracted extensive attention due to their photoresponsive properties. Here, we report a series of novel transition metal coordination networks (CNs): Co-CMNDI, Ni-CMNDI, and Cu-CMNDI, which are constructed from N,N′-bis(carboxymethyl)-1,4,5,8-naphthalenediimide (H2CMNDI) and the corresponding metal salts. The structures were characterized in detail by microanalysis. Structural analysis shows that the frameworks of Co-CMNDI and Cu-CMNDI are 3-periodic fsc nets, while Ni-CMNDI is a 2-periodic sql net. They are sensitive to ultraviolet light, and their color can be changed with a change in the radiation time or intensity. The reversibility of their photochromic behavior and the positive correlation between the color change and ultraviolet intensity makes them possible candidates as UV colorimetric cards in the future. Besides this, the three CNs can be used as fluorescence detectors of three nitroaromatics: p-nitroaniline (PNA), p-nitrophenol (PNP), and p-dinitrobenzene (PDNB), from two emission peaks. At the same time, we introduce a concept of a quenching recognition constant (KQR), which can be used to better compare the recognition effects of the recognizers. The competitive absorption and photoinduced electron transfer between the analytes and recognizer are the main reasons for the fluorescence quenching. This work provides a novel design idea and materials for future multi-functional sensors. [ABSTRACT FROM AUTHOR]

The trans‐dioxido uranyl frameworks named as [(UO2)(Aip)(DMA)] (1), H[(UO2)(Aib)3] (2) and rare cis‐dioxido [(UO2)Co(Suc)2(H2O)4] (3), and [(UO2)Ni(Suc)2(H2O)4] (4) have been synthesized, which based on 5‐aminoisophthalic acid (H2Aip), 3‐aminobenzoic acid (HAib), and succinic acid (H2Suc) as ligands. They were characterized by Fourier Transform Infrared spectra, UV‐vis absorption spectra, single‐crystal X‐ray diffraction, powder X‐ray diffraction and thermogravimetry analysis. It was found that uranium ion of the complex 1 is in the pentagonal bipyramidal coordination environment, while those of the complexes 2–4 are in the hexagonal bipyramidal coordination environment. Complexes 1, 3, and 4 are 3D network structures, 2 is a discrete structure. In particular, geometry of O=U=O for 1 and 2 are trans, ones for 3 and 4 are cis. The highest removal rate of methylene blue was almost to 96 % by complex 1 as an adsorbent, which illustrates that potential application on dye adsorption. [ABSTRACT FROM AUTHOR]

Three co-crystal compounds 1–3 (NDI-A·fluorene) (1), (H3TIBTC·4,4′-bipy) (2), (H3DIBTC·4,4′-bipy) (3) (NDI-A = N,N′-di(4-pyridylacylamino)-1,4,5,8-naphthalenediimide, H3TIBTC = 2,4,6-triiodo-1,3,5-benzene tricarboxylic acid, H3DIBTC = 2,4-diiodo-1,3,5-benzenetricarboxylic acid, 4,4′-bipy = 4,4′-bipyridine) were firstly synthesized by hydrothermal methods. The structural analysis shows that the co-crystal compounds 1–3 have 3D, 2D, and 1D supramolecular structures through hydrogen bonds and π–π interactions. Structural analysis shows that co-crystals 1–3 are constructed into a hydrogen bond ring and chain with graph set notations R 33 (28), R 22 (26), C (8), and R 66 (38), through hydrogen bonds, respectively. Co-crystal 1 has obvious fluorescence properties due to its large conjugate plane. Through the study of the fluorescence emission spectra of NDI-A, fluorene and the co-crystal 1 with their solid lifetimes, the mechanism of luminescence of co-crystal 1 was explored. Based on the good fluorescence properties of co-crystal 1, the detection effect of balsalazide disodium was systematically studied. It was found that co-crystal 1 can qualitatively and quantitatively detect balsalazide disodium under the condition of simulating the ion environment in plasma (Ksv = 8 × 102 M−1; detection limit: 7.25 × 10−5 mol L−1). [ABSTRACT FROM AUTHOR]

Photoresponsive materials are a key part of the age of smart technology that have potential in a broad range of applications. Coordination networks (CNs) are widely used due to their designability and stability. In this work, three novel alkaline earth metal coordination networks (AEM‐CNs): [Mg(CMNDI)(H2O)2], [Ca(CMNDI)(H2O)2]⋅H2O, and [Sr(CMNDI)(H2O)(DMF)] with fsl, cds, and scn topology nets were synthetized via N,N'‐bis(carboxymethyl)‐1,4,5,8‐naphthalenediimide (H2CMNDI); the scn net is not found in the Reticular Chemistry Structure Resource or ToposPro. The reusable and sensitive photochromic properties of the three CNs enable them to be used as secret inks or ultraviolet detectors. In addition, the CNs also exhibited reusable photoluminescent turn‐off toward the drug molecules, balsalazide disodium (Bal.) and colchicine (Col.), with good limits of detection of 0.16 and 0.70 μM. To the best of our knowledge, this is the first study of a fluorescence sensor for Bal. Thus, the AEM‐CNs provide a design idea for integrated photoresponsive materials that could be further improved in the near future by further study. [ABSTRACT FROM AUTHOR]

The field of post‐synthesis modification has aroused widespread concern from diverse perspectives, including chemistry, biology, and material science. Post‐synthesis modification can introduce rich functionality into metal–organic frameworks (MOFs) without destroying the main structure of MOFs. Based on this research status, a series of lanthanide metal–organic frameworks ([Ln2(NH2‐BDC)2.5(CH3COO)(DMA)(H2O)]•DMA, Ln = Pr, Nd, Sm, Eu, Gd and Tb, NH2‐BDC = 2‐aminoterephthalic acid, DMA = N,N‐Dimethylacetamide) with 3D network structures, are synthesized by hydrothermal synthesis. Due to the presence of uncoordinated amino groups in the ligands, a series of post‐synthesis modified compounds are successfully synthesized through aldimine condensation reaction. Based on the good fluorescence properties and stable structure of coordination polymers and post‐synthesis modified compounds in water or organic solvents, they are able to be used as potential fluorescence sensor for the detection of Th4+, UO22+, and Cr2O72−, and the calculation result shows that the post‐synthesis modified compounds are more sensitive to the detection of analytes (Th4+, UO22+ and Cr2O72−) than coordination polymers. In addition, the MOF membrane prepared by self‐assembly of [Eu2(NH2‐BDC)2.5(CH3COO)(DMA)(H2O)]•DMA and ternary soap‐free copolymer (VAc‐AA‐BA) emulsion can be used first for detecting aldehyde vapors. [ABSTRACT FROM AUTHOR]

A liquid matrix is beneficial for improving the luminescence performance of quantum dots (QDs), although it is difficult to be packaged with light-emitting diode (LED) chips. In this study, liquid-QDs with chlorobenzene solution and melamine-modified urea-formaldehyde (MUF) were used as the core and shell structures, respectively, successfully yielding liquid-QD/MUF microcapsules for white LED packaging. The concentration of the liquid-QDs in the microcapsules was optimized, demonstrating an increase of 15.9% in the luminous efficiency, as compared to the traditional solid-QDs at a specific QD energy proportion. The efficiency roll-off can be attributed to the increased reabsorption and back-scattering loss at higher liquid-QDs and microcapsules concentrations. It was also confirmed that the liquid-QD/MUF microcapsules have an excellent thermal stability below 200 °C, owing to the protection of the MUF shells. Finally, white LEDs compounding the red liquid-QD/MUF microcapsules and YAG phosphor particles were fabricated, achieving a high luminous efficiency of 149.2 lm/W at 20 mA, correlated color temperature of 3301 K, and color rendering index of 88.8. This study will open new research avenues for liquid-QD packaging in white LEDs. [ABSTRACT FROM AUTHOR]

Perylenebisimide (PBI)–anthracene (AN) donor–acceptor dyads/triad were prepared to investigate spin–orbit charge‐transfer intersystem crossing (SOCT‐ISC). Molecular conformation was controlled by connecting PBI units to the 2‐ or 9‐position of the AN moiety. Steady‐state, time‐resolved transient absorption and emission spectroscopy revealed that chromophore orientation, electronic coupling, and dihedral angle between donor and acceptor exert a significant effect on the photophysical property. The dyad PBI‐9‐AN with orthogonal geometry shows weak ground‐state coupling and efficient intersystem crossing (ISC, ΦΔ=86 %) as compared with PBI‐2‐AN (ΦΔ=57 %), which has a more coplanar geometry. By nanosecond transient absorption spectroscopy, a long‐lived PBI localized triplet state was observed (τT=139 μs). Time‐resolved EPR spectroscopy demonstrated that the electron spin polarization pattern of the triplet state is sensitive to the geometry and number of AN units attached to PBI. Reversible and stepwise generation of near‐IR‐absorbing PBI radical anion (PBI−⋅) and dianion (PBI2−) was observed on photoexcitation in the presence of triethanolamine, and it was confirmed that selective photoexcitation at the near‐IR absorption bands of PBI.− is unable to produce PBI2−. [ABSTRACT FROM AUTHOR]

A novel lanthanide metal organic framework [(NH2(Me)2)]6·[Tb3(TDPAT)2(μ2-O)1.5]·3EtOH·7.5H2O (complex 1) was constructed via the reaction of 5,5′,5′′-(1,3,5-triazine-2,4,6-triyltriimino) tris(azanediyl) triisophthalate (H6TDPAT) and TbCl3·6H2O. It was well characterized by single-crystal X-ray diffraction, IR spectroscopy, UV-vis spectroscopy, elemental analysis, powder X-ray diffraction (PXRD) and thermogravimetric analysis (TG). Structural analysis confirmed that complex 1 is composed of binuclear building blocks [Tb2(COO)12(μ2-O)] connected by a triazine hexacarboxylic skeleton, which showed an interesting three-dimensional microporous structure. In addition, the fluorescence properties of complex 1 were explored at room temperature. Surprisingly, the results illustrate that complex 1 has outstanding fluorescence properties and can be used as a multifunctional sensor to selectively detect colchicine, some anions, Fe3+ and nitro compounds. Most notably, the detection of colchicine can still be carried out under biological conditions. To our best knowledge, this is the first example of multifunctional fluorescence sensing properties based on the metal organic framework of Tb3+ and triazinehexacarboxylic acid. [ABSTRACT FROM AUTHOR]

This work designed and synthesized seven novel complexes by using transition-metal salts 5-aminoisophthalic acid (5-aip) and 4,4′-bipyridine (4,4′-bipy) by the hydrothermal synthetic method, they were [Zn(5-aip)(4,4′-bipy)0.5]·2H2O (1), [Cu(5-aip)(4,4′-bipy)0.5]·CH3OH (2), [Ni0.25Zn0.75(5-aip)(4,4′-bipy)0.5]·2H2O (3), [Cr(5-aip)(4,4′-bipy)0.5]·2H2O (4), [Co(5-aip)(4,4′-bipy)0.5]·2H2O (5), [Fe(5-aip)(4,4′-bipy)0.5]·2H2O (6), and [Mn(5-aip)2(H2O)2] (7). Complexes 1–7 were characterized by elemental analysis, infrared spectroscopy, UV-vis spectroscopy, powder X-ray diffraction analysis, and thermogravimetric analysis (TG). X-ray single crystal diffraction analysis showed that complexes 1–7 could form a porous three-dimensional network structure through covalent bonding, π–π interaction or hydrogen bonding. In addition, the photodegradation ability of Crystal Violet (CV) solution under natural light was also investigated with complexes 1–4 as the photocatalysts. The results showed that all four complexes had photocatalytic degradation behavior in CV solution. The relationship of the distance between the active sites and the photocatalytic activity was also explored firstly from the fluorescence spectra. The results showed that there was a linear correlation between the photocatalytic activity and the reciprocal of the distance between active sites. The shorter the distance between active sites, the better the photocatalytic degradation effect. And it was found that the photocatalytic degradation process was confirmed to be suitable for the pseudo-first-order kinetic model. [ABSTRACT FROM AUTHOR]

Four amino acid Schiff base complexes—one with a 3D network structure ({[Cd2(PYSA)2(H2O)]·3H2O}n (1)) and the other three with a supramolecular network structure {[Co(PYSA) (H2O)2]·H2O}n (2), {([Zn(PYSA)(H2O)2]·H2O}n (3), {[Mn(PYSA)(H2O)2]·H2O}n (4)), (PYSA = (S-2-(pyridine-4-ylmethylamino) succinic acid)—were successfully obtained under hydrothermal conditions. Among the four complexes, photoluminescence analysis revealed that complex 1 exhibited high selectivity and sensitivity in the detection of iron ions. In particular, it was able to qualitatively and quantitatively detect iron ions at low concentrations without interference from other ions. With a Fe3+ concentration of 0.01 mol/L, the detection limit was 0.81 μM, Ksv = 2.46 × 104 L/mol. In addition, complex 2 exhibited excellent catalytic performance toward 4-nitrophenol (4-PNP). Four amino acid Schiff base complexes 1–4 were synthesized by a hydrothermal method. Among the four, complex 1 exhibited good fluorescence sensing performance in the detection of Fe3+ in water. In addition, the catalytic activity of complex 2 for 4-PNP was preliminarily investigated, which showed an ability to reduce 4-PNP to 4-PAP. [ABSTRACT FROM AUTHOR]

Three luminescent derivatives were synthesized based on improving the synthetic method, including 1,1,2,2-tetrakis(4-bromophenyl)ethylene (1), 4,4′,4″,4′′′-(ethylene-1,1,2,2-tetrayl)tetrabenzoic acid (2), and 4′,4′′′,4′′′′′,4′′′′′′′-(ethylene-1,1,2,2-tetrayl)tetrakis([1,1′-biphenyl]-4-carboxylic acid) (3). They were characterized by elemental analysis, IR spectra, and 1H NMR. Moreover, the specific structure of the compound 1 is determined by single crystal diffraction. We detected the fluorescence responses of the compounds 2 and 3 in different metal ion and nitro compound solutions. It was found that the fluorescence effects of the compounds 2 and 3 for Fe3+ and trinitro phenol (TNP) were so strongest that the fluorescence intensity of the compounds being completely annihilated. In addition, we also studied the fluorescence lifetime and the quantum yield of the compounds 2 and 3, and explained the fluorescence quenching mechanism. [ABSTRACT FROM AUTHOR]

White‐light emitting materials have become a hot research field of luminescent MOF (Metal–Organic Framework) because of its high practical application value. Herein, we successfully synthesized and characterized a rht‐type fluorescent MOF Zn‐TDPAT [H6TDPAT = 2,4,6‐tris(3,5‐dicarboxylphenylamino)‐1,3,5‐triazine] with a topology of (3, 24) connected nodes. A series of MOFs materials x%Tb + y%Eu@Zn‐TDPAT were prepared by incorporating different concentrations of green emission center Tb3+ and red emission center Eu3+ into the blue‐emitting Zn‐MOF. The luminescence properties of MOFs materials x%Tb + y%Eu@Zn‐TDPAT can be effectively adjusted by incorporating different concentrations of Tb3+ and Eu3+ and can obtain multi‐color luminescence properties from blue, blue‐green, green, yellow green, yellow, blue‐red, yellow‐red and white. According to trichromatic mechanism, by reasonably matching the intensity of blue light, green light and red light emitted by x%Tb + y%Eu@Zn‐TDPAT at 420, 543 and 616 nm, MOFs materials 0.75%Tb + 5%Eu@Zn‐TDPAT, 0.65%Tb + 5.5%Eu@Zn‐TDPAT and 0.5%Tb + 7.5%Eu@Zn‐TDPAT with white‐light emission are obtained. Their CIE coordinates are 0.3162, 0.3345 (0.3162, 0.3345), (0.3138, 0.3339) and (0.3329, 0.3222), respectively, which are very close to ideal white‐light emission (0.3333,0.3333). [ABSTRACT FROM AUTHOR]

A facile strategy was used to construct a series of composite materials with color-tunable and white light emission by encapsulating 1,3,6,8-tetrakis(p-benzoic acid)pyrene (H4TBAPy) into framework material [Eu(MCTCA)1.5(H2O)2]·1.75H2O (Eu-MCTCA), which is synthesized based on Eu(NO3)3·6H2O and 5-methyl-1-(4-carboxylphenyl)-1H-1,2,3-triazole-4-carboxylic acid (H2MCTCA). A slight adjustment of the emission color can be easily fulfilled by simply altering the concentration of H4TBAPy or regulating the excitation wavelength. Notably, white light emitting Eu-MCTCA@H4TBAPy can be realized by encapsulating H4TBAPy with a concentration of 0.75 mM, when the excitation wavelength is 350 nm. Furthermore, based on the favorable luminescence and stable structure of Eu-MCTCA@H4TBAPy in water or organic solvents, Eu-MCTCA@H4TBAPy can be used as a potential luminescent probe for detecting Fe3+, Cr2O72− and colchicine. [ABSTRACT FROM AUTHOR]

A novel supramolecular coordination complex [Ag(HMCTCA)(H2MCTCA)] (1) was firstly synthesized by the reaction of a nitrogen heterocyclic organic ligand H2MCTCA (5‐Methyl‐1‐(4‐carboxylphenyl)‐1H‐1,2,3‐triazole‐4‐carboxylic Acid) with AgNO3. It was characterized in detail by some microanalysis means such as elemental analysis, IR, UV, TG and PXRD. Furthermore, the solid fluorescent behavior was explored at room temperature. The results indicated that coordination complex 1 exhibited excellent fluorescent properties. Based on this phenomenon, we discussed its application in fluorescence sensing. The results illustrated that the coordination complex 1 can be applied to detect colchicine and a series of nitro explosives. It is worth noting that coordination complex 1 showed preeminent sensitivity for detecting p‐nitroaniline (PNA), the detection limit was as low as 0.59 μM. [ABSTRACT FROM AUTHOR]

Abstract: Five rare earth-indole carboxylic acid complexes: [Eu(IAA)2(phen)2]·NO3 (1) (IAA = indole acetic acid, phen = o-phenanthroline); [Nd(IAA)2(phen)2]·NO3 (2); [Er(IBA)3(phen)](phen)·HNO3·H2O (3) (IBA = indole butyric acid); [Ce(IBA)3(phen)](phen)·HNO3·H2O (4); [Dy(IBA)3(phen)](phen)·HNO3·H2O (5) were synthesized and characterized. Then, we reported their properties as dye adsorption and fluorescence sensing for the first time. The fluorescence explorations demonstrated that complex 1 exhibits highly selective and sensitive sensing for nitro aromatic compounds with high sensitivity (1.49 × 107 M−1) and low detection limit (11.40 µM). Meanwhile, these complexes also exhibit stronger selective adsorption of dye molecules (MB and MG) in aqueous solution. This study provides new physical insights into the rational design of lanthanide complexes based on multifunctional materials.Graphical Abstract: We firstly reported five lanthanide complexes and displayed fluorescence sensing and selective adsorption dye properties. [ABSTRACT FROM AUTHOR]

Under hydrothermal conditions, four new complexes [InCl2(Hphth)(4,4′-bipy)0.5(H2O)]·2H2O (H2phth = phthalic acid, 4,4′-bipy = 4,4′-bipyridine) (1), [InCl4(4,4′-bipyH)(H2O)] (2), [InCl(Hphth)(nia)(H2O)2] (Hnia = nicotinic acid) (3), [InCl(Hnia)2(Hox)2]·3H2O (H2ox = oxalic acid) (4) were synthesized by the reaction of Indium chloride (InCl3) as the metal source with H2phth, Hnia, 4,4′-bipy and H2ox as the ligands. The single-crystal X-ray diffraction analysis revealed that the complexes 1, 3 and 4 have 3D supramolecular structures with hydrogen bonding interactions and, complex 2 has an extended one-dimensional chain structure, which further forms a 2D supramolecular sheet structure. We discussed and proved the fluorescence sensing functions of these complexes for the different thiamine (TPP, TCl) biomolecules based on a “turn-on” manner. In addition, it is fascinating that these complexes have different potential adsorption characteristics and the adsorption performance of complex 1 was observed to be better than the others. The photoluminescence and dye selective adsorption properties of these complexes have been studied for the first time. [ABSTRACT FROM AUTHOR]

The two compounds UO2(C16H7N4O4)2·2H2O (1) and UO2(C20H12N5O2)2 (2) have been synthesized, based on the different heterocyclic carboxyl ligands 2,3-pyrazino[1,10]phenanthroline-2,3-dicarboxylic acid (H2L1) and 2,6-bis(2-pyrazinyl)pyridine-4-benzoic acid (HL2). The two compounds were characterized by elemental analysis, IR spectroscopy, PXRD, thermogravimetric analysis and UV-visible spectroscopy. Single crystal X-ray diffraction analysis revealed that both compounds 1 and 2 exhibited 2D sheet structures. Moreover, the study of fluorescence quenching properties of compounds 1 and 2 showed that luminescence intensity decreases for both 1 and 2 were especially obvious with increasing of nitroaromatics concentration, even if the nitroaromatics were at a very low concentration (for 1 it is 15 ppm, for 2 it is 20 ppm), which can also be detected. The experimental results suggest a high selective quenching of initial fluorescence intensity in the presence of nitroaromatic compounds. And by calculating the quenching constants of the nitroaromatics using the SV equation (I0/I) = KSV[A] + 1, we can see the KSV values of the quencher 2,4,6-trinitrophenol are both largest for the two compounds, and the values are 1.6 × 106 and 8.5 × 105 for 1 and 2, respectively. This means that the two compounds have the most sensitive luminescence. In addition, compound 2 exhibits enhanced fluorescence behavior towards aldehyde compounds, showing a turn-on fluorescence responsive behavior. [ABSTRACT FROM AUTHOR]

By selecting appropriate ligands, two polyoxidovanadate complexes, [Ni(en)2]3[V18O42Cl]·7H2O·2H3O+(1) and [H2N(CH3)2]3[PV14O42]·2TMP·6H3O+(2), have been synthesized at different pH values using V2(SO4)3, Ni(CH3COO)2, and H6TTHA (for1), VO(acac)2and TPP (for2) (en = C2H8N2, TPP = thiamine pyrophosphate, TMP = thiamine monophosphate, H6TTHA = 1,3,5-triazine-2,4,6-triamine hexaacetic acid). The complexes have been characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis (TG), and single crystal X-ray diffraction. The complexes catalyze the oxidation of the organic substrate phenol red in the presence of H2O2and bromide, and the reaction system is considered as a model for hydrogen peroxide determination. The reaction rate constants (k) for1and2are calculated as 3.729 × 103and 4.083 × 103(mol L)−2 s−1. The maximum conversion rate of phenol red for1is 83.32%, while for2is 81.12%. [ABSTRACT FROM AUTHOR]

Four uranyl complexes (UO2)2(pht)2(Hpac)2(H2O)2 (pht = phthalic acid and Hpac = nicotinic acid) (1), (UO2)(pac)2(H2O)2 (2), [(UO2)(CMA)3]·[H2N(CH3)2] (CMA = cinnamic acid) (3) and (UO2)2(C2O4)(μ2-OH)2(H2O)2·H2O (4) were synthesized by the reaction of UO2(CH3COO)2·2H2O as the metal source with phthalic acid, nicotinic acid, cinnamic acid or oxalic acid as the ligand. They were characterized by elemental analysis, IR, UV-vis, XRD, single crystal X-ray diffraction and thermal gravimetric analysis. The structural analysis showed that complexes 1, 2 and 3 were discrete structures, and by hydrogen bonding interactions, the adjacent molecular units are connected to form a three-dimensional (3D) supramolecular network structure for complex 1 and one-dimensional (1D) chains for complexes 2 and 3. Meanwhile, in the structure of complex 4, a tetrameric SBU (UO2)4(μ2-OH)4(H2O)4 is linked to a 2D layer through a bridging oxalic acid ligand, and furthermore extends the 2D layer into a 3D supramolecular architecture by hydrogen bonding interactions. In order to extend their functional properties, their photoluminescence, surface photovoltage and mixed-dye selective adsorption properties have been studied for the first time. Through experiments, we found that the adsorption performance of complex 3 was better than others, and the amount of adsorbed RhB was 4.22 mg g−1. [ABSTRACT FROM AUTHOR]

[Cu2(UO2)4(suc)4(pac)4] (1), [(Cu(H2O)2)(4,4′-bipy)2][(UO2)2(H2O)2(Hca)2]·3H2O (2), and [(Cu(H2O)2)(UO2)(bta)]·4H2O (3) were synthesized by the reaction of succinic acid and 3-pyridinecarboxylic acid, citric acid and 4,4′-bipyridine, or 1,2,4,5-benzenetetracarboxylic acid ligands with Cu(NO3)2·3H2O and UO2(CH3COO)2·2H2O. The complexes were characterized by IR and UV–vis spectroscopy, powder X-ray diffraction, single-crystal X-ray diffraction, and photoluminescence spectroscopy. Photocatalytic activities of the complexes were also investigated. [ABSTRACT FROM PUBLISHER]

Vanadium(iii) complexes [V(2,6-pdc)2(H2O)2]·2H2O (1) and V(2,6-pdc)(htba)(H2O)2 (2), (2,6-pdc = 2,6-pyridinedicarboxylic acid, htba = 2-acetoxy-4-trifluoromethylbenzoic acid) have been synthesized by the reaction of V2(SO4)3 with 2,6-pdc (for 1) or 2,6-pdc and htba (for 2) under hydrothermal conditions at 120 °C for 36 hours. Because the vanadium(iii) was easily oxidized into higher oxidation states, we included the reducing agent vitamin C to protect the vanadium(iii) center. The complexes were characterized by elemental analysis, IR and UV-vis spectroscopy, and single-crystal X-ray diffraction. Structural analysis revealed that the central metal V atoms in the complexes 1 and 2 were seven-coordinate, forming pentagonal bipyramid geometries. The complexes catalyzed the bromination of the organic substrate phenol red in the presence of H2O2, bromide and buffer. Compared with vanadium complexes having other oxidation states, the vanadium(iii) complexes had better catalytic activity (the maximum reaction rate constant was 2.424 × 102k(mol L−1)−2 s−1). The mimicking vanadium haloperoxidases also overcame some serious disadvantages of natural enzymes. Therefore, the reaction system described herein can be considered as an effective model for hydrogen peroxide determination. [ABSTRACT FROM AUTHOR]

Six novel coordination polymers {Co(HCOO)(4,4′-bipy)} ( 1), {[Ni(4,4′-bipy)(OH)(HO)]·suc·2HO} ( 2), {Ni(HCOO)(4,4′-bipy)} ( 3), {Zn(HCOO)(4,4′-bipy)} ( 4), {Cu(HCOO)(4,4′-bipy)} ( 5) and {[Cu(ox)(2,2′-bipy)]·2HO} ( 6) (suc succinic acid, ox oxalic cid) based on pyridine derivatives and carboxylates as ligands were designed and synthesized. The coordination polymers were characterized by elemental analysis, IR and UV-Vis spectra, powder X-ray diffraction, the thermo gravimetric analyses and single-crystal diffraction analysis. The structure analysis showed that the central metal atoms in coordination polymers 1, 2, 3, 4 and 6 all were six-coordination modes, forming distorted octahedron geometries. Cu atom in the coordination polymer 5 was four-coordination mode, forming square planar coordination geometry. While in the coordination polymers 1, 3 and 4, two metal centers were connected by bridging coordination fashions of formic acid ligand, forming a three-dimensional network structure, and in the coordination polymer 6, the two metal centers were connected by bridging coordination fashions of oxalic acid ligand, forming one-dimensional chain. In addition, the photocatalytic activity of a series of covalent heterojunction coordination polymers was studied. [ABSTRACT FROM AUTHOR]

Four uranyl complexes [(UO2)(pht)H2O]·H2O (pht = phthalic acid) (1), (UO2)2(Hipa)4(H2O)2 (Hipa = isophthalic acid) (2), (UO2)(tpa)(DMF)2 (tpa = terephthalic acid) (3) and (UO2)(box)2 (box = benzoic acid) (4) were synthesized by the reaction of UO2(CH3COO)2·2H2O as the metal source and phthalic acid, isophthalic acid, terephthalic acid or benzoic acid as the ligand. They were characterized by elemental analyses, IR, UV-Vis, XRD, single crystal X-ray diffraction analysis and thermal gravimetric analysis. The structural analysis reveals that complex 1 exhibits a one-dimensional chain structure constructed by the building unit [(UO2)2(pht)4(H2O)2] and further extends the chain into a 2D supramolecular architecture by hydrogen bonding interactions. Complex 2 is a discrete [(UO2)2(Hipa)4(H2O)2] structure, and by the hydrogen bonding interaction, forms a 3D supramolecular structure. In complexes 3 and 4, adjacent uranyl polyhedra form a 1D chain through bridging terephthalic acid and benzoic acid, respectively. In order to extend their functional properties, their photoluminescence, surface photovoltage and dye adsorption properties have been studied. [ABSTRACT FROM AUTHOR]