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• Three modified UIO based multivariate metal-organic framework synthesized. • These MOFs characterized using different physico-chemical techniques. • Their photocatalytic properties against aromatic dyes assessed under UV light. • The plausible mechanistic pathways by which CPs executed photodegradation of dyes explained with the aid of band gap calculations. The photocatalytic activity of a series of UIO-66 modified MOFs viz. UiO-66-NO 2 [ 1 ], UiO-66-NH 2 [ 2 ] and UiO-66-NO 2 /UiO-66-NH 2 [ 3 ] materials for photocatalytic degradation of model aromatic dye Rhodamine B [Rh B] have been assessed. The photocatalysis experiments indicated that the most efficient photocatalyst for the Rh B degradation is 3 which achieved 95.5% degradation under UV light irradiation and displayed excellent recyclability and reusability when compared to 1 and 2. The trapping experiments indicated that O 2 ˙− radical anion is main ROS generated during the photocatalysis play major role in the Rh B degradation. The LC-MS experiments and band gap calculations have been performed which suggested initial protection of xanthene unit and confirmed the major contribution of O 2 ˙− radical anion generated by ligand to ligand transition in 3 for photodegradation of Rh B. This facile approach inculcating benefits of mixed ligands in multivariate metal-organic framework, lays a new pathway to design effective photocatalytic systems for safe and sustainable degradation of aromatic dyes. This strategy led to suppression in rate of hole-electron pair recombination that concomitantly uplifted photocatalytic efficiency over single component counterparts. Three mixed ligand multivariate modified UIO based metal-organic framework synthesized for enhanced UV-light photocatalytic degradation of aromatic dyes. [Display omitted] [ABSTRACT FROM AUTHOR]

In keeping with our current interest in pyridine-based multifunctional metal-organic frameworks (MOFs), we presented a Zn(II)-based MOF [Zn(HL) (bpe)] (1) by the employment of pyridine ligand and flexible aromatic carboxylic acid. The single-crystal X-ray diffraction analysis reveals that 1 shows 6-connected diamond net with a Schläfli symbol of (66). Furthermore, MOF 1 was employed as a photocatalyst for the oxidation of hazardous antibiotic molecules viz. Nitrofurazone (NFZ), dimetridazole (DTZ), and oxytetracycline (OXY) in an aqueous medium, amongst which the MOF exhibited the best photocatalytic decomposition performance against NFZ with a degradation efficiency of 82.63%.The Hirshfeld surfaces analysis demonstrated that this synthesized MOFs contain various forms of intermolecular contacts (C⋯C, H⋯C, H⋯H, and O⋯H). MOF 1 exhibits extremely promising photocatalytic degradation of hazardous antibiotics molecules, the mechanism was also explored in detail. [Display omitted] •The degradation efficiency of NFZ by 1 was very high compared to other antibiotic. •Hirshfeld norm surface of carboxylate are mainly covered by H⋯O/O⋯H, C⋯H/H⋯C and H⋯H interactions. •The possible photodegradation mechanism is proposed according to the free radical and hole trapping experiments. [ABSTRACT FROM AUTHOR]

A new Zn(ii) metal–organic framework, formulated as {[Zn(L)]·2.7 DMF} (1), was synthesized using a multidentate ligand 1,4-bis(triazol-1-yl)terephthalic acid (H2L). The MOF 1 adopts 3D uninodal 4-c CdSO4 topology and behaves as a luminescent chemosensor for highly selective and sensitive detection of Fe3+ and nitro-aromatics, particularly 2,4,6-trinitrophenol (TNP). In addition, the thermal stability, UV/Vis diffuse-reflection spectra and photocatalytic behaviors of 1 against organic dyes have also been investigated. The possible mechanism associated with the alleviation in the emission intensity of 1 in the presence of nitro-aromatic compounds were addressed by theoretical calculations. In addition, the photocatalytic activity of 1 against organic dyes was addressed using density of states (DOS) calculations. [ABSTRACT FROM AUTHOR]

A new metal–organic framework, formulated as {[Zn2(L)(DMF)3]·2DMF·2H2O} (1), has been synthesized using a symmetrical rigid carboxylate ligand terphenyl-3,3′′,5,5′′-tetracarboxylic acid (H4L). Single-crystal X-ray diffraction analysis shows that 1 possesses a 3D uninodal 4-c lonsdaleite (lon) topology based on binuclear Zn clusters. 1 behaves as a fluorescent chemosensor for highly selective and sensitive detection of Fe3+/Fe2+ ions, 2,4-dinitrophenol (2,4-DNP), p-nitrophenol (PNP) and 2,4,6-trinitrophenol (TNP). Furthermore, the photocatalytic properties of 1 for degradation of methyl violet (MV) and Rhodamine B (RhB) have been explored. The possible emission quenching of 1 in the presence of aromatic compounds has been addressed by theoretical calculations and the photocatalytic activity of 1 against organic dyes has been addressed using density of states (DOS) calculations. [ABSTRACT FROM AUTHOR]

Two new zinc(II) metal–organic compounds of [Zn(ADC)(bimh)] n ( 1 ) and [Zn(ADA)(bimh)] n ( 2 ) (H 2 ADC = 1,3-adamantanedicarboxylic acid, H 2 ADA = 1,3-adamantanediacetic acid, bimh = 1,6-bis(2-methyl-imidazole-1-yl)-hexane, have been structurally characterized by X-ray diffraction analysis. In compound 1 , the zinc(II) ions are bridged by ADC and bimh ligands to form a 1D looped chain. In compound 2 , the ADA molecules alternately bridge Zn(II) atoms to form infinite chains, and then the 1D chain is connected through the bimh ligand resulting in an undulating infinite two-dimensional (2D) polymeric network. Additionally, TG analysis, XRPD and fluorescent properties for compounds 1 and 2 are also measured and discussed. [ABSTRACT FROM AUTHOR]

Two new zinc(II) metal-organic compounds, {[Zn(ADC)(bib)]·CH3OH·H2O}n(1) and [Zn(ADA)(bib)]n(2) (H2ADC = 1,3-adamantanedicarboxylic acid, H2ADA = 1,3-adamantanediacetic acid, bib = 1,4-bis(2-methyl-imidazol-1-yl)butane), have been synthesized and characterized. In1, zinc(II) ions are bridged by ADC to form a 1-D chain. The chains are further connected by bib to form a 2-D wave structure. In2, zinc(II) ions are bridged by two ADA to form a 1-D looped chain, and then the 1-D looped chain is connected through bib resulting in a 2-D network. Fluorescent properties, TG analysis, and XRPD for1and2are also measured and discussed. [ABSTRACT FROM PUBLISHER]

Two new metal–organic compounds, [Ag2(HADC)2(bimh)] (1) and [Cd(ADC)(bpp)]n(2) [H2ADC = 1,3-adamantanedicarboxylic acid, bimh = 1,6-bis(2-methyl-imidazole-1-yl)hexane, bpp = 1,3-bis(4-pyridyl)propane], have been synthesized and characterized. Compound1exhibits a discrete symmetric unit with 0D?2D interpenetrating structure. Compound2crystallizes in a chiral space groupP212121and presents a threefold interpenetrated 3D diamondoid network containing three helical chains. Thermal stability, X-ray powder diffraction, and luminescence for1and2are also measured and discussed. [ABSTRACT FROM PUBLISHER]

Abstract: A new 3D helical silver(I) metal–organic polymer of {[Ag2(ADC)(bib)0.5]·H2O}n (1) (H2ADC=1,3-adamantanedicarboxylic acid, bib=1,4-bis(2-methyl-imidazol-1-yl)butane), has been synthesized and characterized. Compound 1 exhibits significant void space that may be filled with guest H2O molecules in spite of the metal-cluster that occurs in the solid. Preliminary thermal and fluorescence experiments show that compound 1 possesses strong fluorescent property and thermal stability, respectively. [Copyright &y& Elsevier]

The solvothermal reaction of hexa -caboxylic ligand and Zn(II) result in an unique and novel trinuclear porous luminescent coordination polymer with 3,4,6-connected structure. It is noteworthy that one carboxyl group is not protonated from H 6 dpa ligand, which may function as the potential active sites. The photoluminescence studies show that 1 can exhibit highly effective and selective luminescent sensing for pesticide chlorpyrifos in aqueous solution, which make its good candidates as luminescent sensors. • Through design, a novel trinuclear Zn(II) porous luminescent complex was obtained. • Compound possesses strong fluorescent property and thermal stability. • Compound exhibits highly selective to chlorpyrifos through luminescence quenching. A new trinuclear porous luminescent coordination polymer with 3,4,6-connected, {[Zn 3 (Hdpa)(OH)(H 2 O) 2 ]·6H 2 O} n (1) (H 6 dpa = 3, 4-di(3,5-dicarboxyphenyl)phthalic acid), has been synthesized and characterized. Compound 1 contains one unprotonated carboxyl group that can function as a potential active site. Moreover, Luminescent investigations show that 1 exhibits highly effective and selective luminescent sensing for pesticide chlorpyrifos in aqueous solution, which makes its good candidates as luminescent sensors. [ABSTRACT FROM AUTHOR]

• A new 3D PbII-based MOF having 4,4'-sulfonyldibenzoate synthesized and characterized • It displays uninodal (3,6)-connected topology with point symbol {62.8}{46.67.82}. • The MOF works as luminescent sensor for sensitive and selective detection of furazolidone. • Recovery in the emissive response of FZD@ 1 have been demonstrated in the presence of salicylic acid. • The mechanism for the decline and restoration of emissive response of 1 have been explained with the help of theoretical calculations. A new 3D PbII-based metal-organic framework (MOF) [Pb(SDBA)] n ·1.75DMF (1) (SDBA = 4,4'-sulfonyldibenzoate) has been synthesized and characterized. The single crystal X-ray diffraction study reveals that 1 is a uninodal (3,6)-connected topology with a point symbol of {62.8}{46.67.82} based on 1D Pb–O–Pb chain. The MOF 1 has been employed as luminescent sensor for sensitive and selective detection of antibiotics and experiments suggest that 1 can selectively and sensitively recognize furazolidone (FZD) with limit of detection (LOD) of 1.01 × 10-6 M and shows recyclable sensing properties against FZD. Interestingly, FZD could be directly detected with naked eyes under 365 nm UV lamp using paper test strips impregnated with 1. Also, complete recovery in the emissive response of FZD@ 1 has been demonstrated in the presence of salicylic acid. This is only the second example of PbII-based MOF that has been employed as turn-off-on fluorescent sensor towards FZD. The plausible mechanisms for the decline and restoration of emissive responses of 1 have been explained with the help of Hirshfeld surface analysis and density functional theory. [Display omitted] A new Pb(II)-based MOF synthesized and used as turn-off-on sensor against furazolidone. [ABSTRACT FROM AUTHOR]

• A new Cd(II)-based MOF with a new (3,4,5)-connected topology was synthesized. • The MOF exhibits best photocatalytic degradation of NFT upto to ∼99.66% within1 h. • The effects of initial concentration of NFT and photocatalyst dosage on the photocatalytic performance of 1 have been studied. • The plausible photocatalytic mechanism by 1 to photodegrade NFT has been proposed using density of states plot and Hirshfeld surface analysis. A new Cd(II)-based MOF with composition [Cd 3 (bpyp) 3 (HCOO) 4 (H 2 O) 2 ·2NO 3 −] n (1) (bpyp = 2,5-bis(pyrid-4-yl)pyridine) have been synthesized and characterized by single crystal X-ray diffraction and FTIR spectroscopy. The MOF 1 forms 3D framework comprising elliptical channels of size 5.1×8.8 Å along the c- axis and possess (3,4,5)-connected topology. The MOF have been employed as catalyst for photodegradation of antibiotics such as nitrofurantoin (NFT), nitrofurazone (NFZ) and furazolidone (FZD). Amongst, these antibiotics, the MOF exhibits best photocatalytic degradation of NFT upto to ∼99.66% in 1 h. The photocatalytic efficacy of MOF 1 against antibiotics follows the order NFT > NFZ > FZD. The impact of NFT concentration as well as photocatalyst dosage on catalytic efficacy of 1 have been explored. These experiments suggest that most appropriate reaction conditions for 1 assisted photodecomposition of NFT are 5 mg dose of 1 and 40 ppm starting NFT amount. The reactive oxygen species (ROS) quenching experiments suggest that superoxide (O 2 ·−) is majorly responsible for NFT decomposition. The plausible mechanism employing which the MOF 1 photodegrades NFT has been explained by density of states plot and Hirshfeld surface analysis. Further, LCMS studies have been performed to explore the possible intermediates formed during photodegradation of NFT. [Display omitted] A new Cd(II)-based MOF with 2,5-bis(pyrid-4-yl)pyridine) ligand synthesized and characterized and used as photocatalysts for photodegradation of antibiotics. [ABSTRACT FROM AUTHOR]

A new Mn(II)-based MOF exhibited an impressive 96.81% degradation of NFT. A proposed photodegradation mechanism was investigated through radical trapping experiments. [Display omitted] • 1 exhibits a new 3D porous network with a (3,4,5)-connected topology. • It as photocatalysts against NFT antibiotics degradation. • Effects of photocatalyst and antibiotics concentrations were discussed. • A proposed photodegradation mechanism was investigated in detail. The synthesis of a new Mn(II)-based metal–organic framework (MOF), denoted as [Mn 3 (bpyp) 3 (HCOO) 4 (H 2 O) 2 ·2NO 3 –·H 2 O] n (1) (bpyp = 2,5-bis(pyrid-4-yl)pyridine) was confirmed by single-crystal X-ray diffraction (XRD), UV–visible, Fourier-transform infrared spectroscopy (FT-IR), and thermogravimetric analysis (TGA). 1 exhibits a new 3D porous network with a (3,4,5)-connected topology. The photocatalytic degradation capability of 1 was investigated against various antibiotics, including dimethonidazole (DTZ), nitrofurazone (NFZ), nitrofurantoin (NFT), tinidazole (TDZ), and furazolidone (FZD). 1 exhibited exceptional photocatalytic activity against NFT, with a dosage of 5 mg/L resulting in a remarkable degradation efficiency of 96.81 % for 40 ppm NFT. Furthermore, a proposed photodegradation mechanism was investigated through radical trapping experiments, providing insights into the underlying pathways involved in the photocatalytic degradation process. [ABSTRACT FROM AUTHOR]

• A new 3D Zn(II) MOF synthesized and characterized. • The MOF was used as photocatalysts against dye degradation. • The MOF exhibited best photocatalysis against methyl blue. • Effect of photocatalyst and dye concentrations on photocatalysis investigated. A new 3D Zn(II)-based metal-organic framework [(CH 3) 2 NH 2 ] 2 [Zn 5 (TTC) 4 ] (1) (H 3TTC = 2,2′:6′,2″-terpyridine-4,4′,4″-tricarboxylic acid) has been solvothermally synthesized and characterized. The single crystal X-ray diffraction for 1 indicate that it possess (3,4,4)-connected network with Schläfli symbol (4.84.10) 4 (84.102) 4 (4.82). Apart from the structural investigation, the photocatalytic performance of MOF 1 to photo-decompose aqueous solution of model dyes viz. methyl violet (MV), Rhodamin B (Rh B), acetylene carbon black (ACB) and methyl blue (MB) have been examined. The photodecomposition results suggest the Zn(II)-MOF based catalyst exhibits best potential to photodegrade MB dye under UV light irradiation. Effect of photocatalyst dosage and initial MB dye concentration on the photocatalytic properties suggest that the photocatalyst exhibits best activity at 50 mg photocatalyst dosage and 18 ppm of initial dye concentration. The plausible photocatalytic mechanistic pathway of MB dye in the presences of 1 has been established with the aid of trapping experiments and density of states (DOS) calculations. A porous 3D Zn(II)-MOF synthesized and used as photocatalyst for dye degradation. [Display omitted] [ABSTRACT FROM AUTHOR]

The photocatalytic properties of d 10 -based metal-organic frameworks (MOFs) have been developed as a potential technology in the photo-degradation of organic dyes. Herein, a biocompatible metal-organic framework (MOF) {[Zn 2( fer) 2 ]∙0.5H 2 O} n ( 1 ) (fer = ferulic acid) has been selected which shows photocatalytic activity for the degradation of methyl violet (MV) and Rhodamine B (Rh B) in aqueous solution under UV irradiation. The photocatalytic results indicated the 1 exhibit 88% photocatalytic efficiency against Rh B in 100 min, while its against MV was only 54% under the identical experimental conditions. Moreover, a possible mechanism for the photocatalytic activity has proposed by density of states (DOS) calculations. [ABSTRACT FROM AUTHOR]

Complex 1 showed a stable activity for methyl violet (MV) degradation and its plausible mechanism was investigated by using various scavengers. • A new bimodal (4, 6)-connected network was obtained. • 1 showed a stable activity for methyl violet (MV) degradation. • This study demonstrates that flexible MOFs can be engineered to display intrinsic photocatalytic activity. Metal–organic frameworks (MOFs) have considered as a class of crystalline porous materials, which provides an advanced platform to develop catalysts for the photocatalytic dyes from wastewater. Herein, a new twofold interpenetrating MOF namely, {[Co 2 (bdc) 2 (bmp) 1.5 ]·DMF·1.5H 2 O} n (1) was synthesized by the hydrothermal reaction (bmp = 1,3-bis(2-methylimidazolyl)pentane, H 2 bdc = 1,3-benzenedicarboxy acid). 1 exhibits a bimodal (4, 6)-connected network with a Schläfli symbol of (43.63) 2 (46.66.83). 1 showed a moderate activity for methyl violet (MV) degradation after four consecutive usages. MV degradation over the title MOF photocatalyst follows first order kinetics. Finally, the plausible mechanism was investigated by using various scavengers. [ABSTRACT FROM AUTHOR]