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Manganese-based Metal-organic Frameworks (Mn-MOFs) represents a unique sub-class of MOFs with low toxicity, oxidative ability, and biocompatibility, which plays vital role in the application of this class of MOFs in medical field. Mn-MOFs show great potential in biomedical applications, and has been extensively studied as compared to other MOFs in transition metal series. They are important in medical applications because Mn(II) possess large electron spin number and longer electron relaxation time. They display fast water exchange rate and could be employed as a potential MRI contrast agent because of their strong targeting ability. Manganese complexes with different ligands also display prospective applications in area such as carrier for drug targeting in anti-tumor and antimicrobial therapy. In the review presented herewith, the application of Mn-based complexes and Mn-MOFs have been emphasized in the area such as imaging viz. MRI, multimodal imaging, antitumor activities such as chemodynamic therapy, photodynamic therapy, sonodynamic therapy and antimicrobial applications. Also, how rational designing and syntheses of targeted Mn-based complexes and Mn-MOFs can engender desired applications., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Metal–organic frameworks (MOFs), a sub-class of well-known coordination polymers, are assorted multidimensional materials that can be employed as photocatalysts for the decomposition of aromatic dyes present in wastewater discharge. Herein, two new Cd(II) MOFs [Cd7(L)4(μ2-OH)2(H2O)4(bbi)3] (1) and [Cd3(L)2(bbm)2] (2) (H3L = 3-(4-carboxyphenoxy)-5-methylbenzoic acid, bbi = 1,4-di(1H-imidazol-1-yl)butane and bmp = 1,3-bis(2-methylimidazolyl)pentane) have been synthesized and characterized. Single-crystal X-ray diffraction analysis reveals that 1 possesses a 3D (3,16)-connected pillar-bilayer network with a {32·4}2{38·450·534·624·74} topology and comprises [Cd7(COO)14] SBUs. Meanwhile, 2 exhibits a 2D (3,8)-connected framework with a {3·42}2{34·46·56·68·73·8} topology comprising [Cd3(COO)6] SBUs. Both MOFs have been used as photocatalysts for the photodegradation of aromatic dyes, and experiments demonstrate that 1 and 2 exhibit 95.5% and 86.2% photodegradation of methyl violet (MV), respectively, in a time span of 100 min. Moreover, both MOFs offer better photodegradation of MV than other model dyes such as rhodamine B, methyl blue and methyl orange. Additionally, the effects of catalyst amount and dye concentration on dye degradation have been explored. Further, trapping experiments indicate that ˙OH and ˙O2− are the active species responsible for the degradation of MV in the presence of 1. Both MOFs could be recycled and used repeatedly as photocatalysts for the degradation of MV, which showcases their highly stable nature. Density of states plots and Hirshfeld surface analyses have been performed to address the plausible photocatalytic mechanistic pathways. [ABSTRACT FROM AUTHOR]

Porous crystalline materials (PCMs) constitute a class of covalent or supramolecular coordination architectures having intensive application in the fields of sensing, gas separation and storage, catalysis and optoelectronic device engineering. The theoretical investigations on these porous crystalline systems using multiple wave functions add fundamental insights into better understanding of highly selective sensing. A lot of recent reports focus on various archetypal luminescent porous organic frameworks, like metal organic frameworks (MOFs), covalent organic frameworks (COFs), or nanocomposites having excellent luminescence sensing performance against a plethora of nitroaromatic compounds and explosives. These exceptional classes of compounds display unique characteristic photochromism and electronic properties which can be tuned from the grass-root level by modifying metal–ligand interactions and various supramolecular interactions at the molecular level. Thus, developing luminescent porous organic frameworks having ultra-fast capacity of sensing nitroaromatic compounds and explosives reversibly with high selectivity and low limits of detection (LOD) is urgently required for national security, as well as homeland and environment safety. The reusability of these porous frameworks can only be anticipated if the crystallinity of these materials is retained after repeated use followed by construction of these frameworks with cheaper starting materials. The present review mainly encompasses the recent progress in various luminescent PCMs incorporating transition metals, lanthanides, nanocomposites, and main group elements having sensing technology applications along with the theoretical insights and possible mechanisms behind "turn-on" or "turn-off" luminescence. [ABSTRACT FROM AUTHOR]

A new d10-configuration based Zn(ii) 3D metal–organic framework (MOF) with the formula {[Zn4(NDC)3.5(μ4-OH)(DMF)]·1.7DMF}n (1) has been synthesized using a 1,4-naphthalenedicarboxylic acid (H2NDC) ligand and characterized. The single crystal X-ray diffraction results indicate that in the newly synthesized MOF, 7-connected [Zn4(μ4-OH)(COO)7] clusters are formed which are extended by NDC2− ligands to generate an uncommon sev topology. The photocatalytic properties of 1 in the photodegradation of model organic dyes viz. methyl violet (MV) and rhodamine B (Rh B) have been systematically investigated. The photocatalysis results demonstrated that 1 shows promising photocatalytic degradation activity against these organic dyes. The possible photocatalytic mechanism through which 1 displayed photocatalytic properties to photodegrade organic dyes has also been proposed with the aid of density of states (DOS) calculations. [ABSTRACT FROM AUTHOR]

The articulate combination of intriguing functional groups and luminescence properties can deliver metal–organic frameworks (MOFs) with multifarious applications viz. selective and specific sensing of nitroaromatic compounds (NACs), an important constituent of explosives, as well as sensing of toxic metal ions. In this regard, a new d10 configuration based Zn(ii) metal–organic framework (MOF) {(NH2(CH3)2)[Zn4(ddn)2(COO)(H2O)4]·solvent}n (1) has been synthesized using a π-conjugated and rigid multicarboxylate ligand 3,5-di(3,5-dicarboxylphenyl)nitrobenzene (H4ddn). 1 displays a 3D (3,4,6)-c connected net which is based on two types of binuclear [Zn2(μ2-COO)2(μ1-COO)2] and [Zn2(μ2-COO)4] clusters. Sensing studies of 1 to detect nitro-aromatic compounds reveal highly specific detection of 2,4-dinitophenol (DNP) with remarkable quenching (KSV = 8.93 × 103 M−1) and a low limit of detection (LOD: 1.12 ppm). The luminescence quenching mechanism in the case of 1 in the presence of NACs has been ascribed to the concurrent presence of the charge transfer as well as the weak interaction between the MOF and NACs. The activated framework of 1 also displayed highly selective detection of ferric ions with KSV = 1.13 × 104 M−1 with a low limit of detection (LOD: 1.24 ppm). [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 Cd(ii) based metal–organic framework (MOF), having formula {(CH3)2NH2)6[Cd5(L)4]·H2O·3DMF}n (1), has been synthesized based on a rigid tetracarboxylate ligand of terphenyl-3,3′′,5,5′′-tetracarboxylic acid (H4L). 1 shows a complicated 3D tetranodal 3,3,4,8-c network with uncoordinated –COO− groups. The highly selective luminescent sensing of 2,4-dinitrophenol (2,4-DNP), 2,4,6-trinitrophenol (TNP) and ferric ions was studied for 1 through the alleviation in its fluorescence intensity. The detection limit of 2,4-DNP was found to be 0.84 ppm, which is 20 times higher than that of 1,3,5-trimethylbenzene, demonstrating greater and selective quenching ability. The possible mechanism associated with the decrease in fluorescence intensity of 1 in the presence of nitroaromatics (NACs) has been addressed by theoretical calculations. Furthermore, 1 displays excellent capacity to adsorb methylene blue (MB) with high selectivity, and it maintains an almost identical adsorption performance after being recycled five times. [ABSTRACT FROM AUTHOR]

A new 3D MOF was synthesized and characterized and its photocatalytic properties to photo-degrade the methyl violet were explored. • Title MOF shows 3D framework with a rare (4,6,6)-connected topology. • The materials display good photocatalytic property. • The plausible mechanism of the photocatalytic activities have been proposed. A new metal-organic framework of [Mn 4 (L) 2 (4,4′-bipy) 2 (H 2 O) 4 ]·(H 2 O)(4,4′-bipy)] (1) has been synthesized using a symmetrical tetracarboxylate 5-[bis(4-carboxybenzyl)-amino]isophthalic acid (H 4 L) and 4,4′-bipyridine (4,4′-bipy) coligands. The single crystal X-ray diffraction study indicates that in 1 , the Mn(II) centers are bridged by L4− and 4,4′-bipy ligands to furnish a 3D framework with a rare (4,6,6)-connected (4.53.62) 2 (42.54.66.72.8}{57.66.82} topology. 1 exhibits related lower photocatalytic activity for degradation of organic dye methyl violet (MV) under UV light and offers good stability after performing photocatalysis. A mechanism for the photcatalytic property of MOF is proposed, which is based on the results of density of states (DOS) and partial DOS calculations. [ABSTRACT FROM AUTHOR]

Abstract The intelligent blending of intriguing functionalities in ligands and incorporation of spectroscopically silent metal cations can produce metal-organic frameworks (MOFs) with multifarious applications viz. selective and specific sensing of nitroaromatic compounds (NACs) an important constituent of explosives as well as photocatalytic properties. A new 3D Zn(II)-based metal-organic framework, [Zn 4 (μ 2 -OH) 2 (BDC) 3 (bip) 2 ] (1) have been synthesized using a mixed ligand strategy using benzene-1,3-dicarboxylic acid (H 2 BDC) and 1,4-bis(2-methyl-imidazole-yl)-propane (bip) and zinc nitrate via hydrothermal reaction. The framework of 1 adopts a 5-connected 3D network with the Schläfli symbol {33.4.52.62.72}. The luminescent sensing investigation indicated that 1 can behave as a luminescent sensor for highly sensitive detection of nitroaromatics (NACs) especially against 2,4,6-trinitrophenol (TNP). The possible depletion in the photoluminescence intensity of 1 in presence of NACs have been addressed using theoretical calculations which indicated that charge transfer as well as the weak interaction between NACs and MOF may be responsible for the decline in the photoluminescence intensity. The MOF have been used as the photocatalyst for the decomposition of methyl violet (MV). Also, the mechanism for the photocatalysis have been addressed using density of states (DOS) calculations. Graphical abstract A highly luminescent Zn(II) 3D MOF synthesized and its sensing properties against nitroaromatics and photocatalysis against aromatic dye explored. Image 1 Highlights • A 5-connected Zn(II)-based 3D MOF was synthesized. • Its luminescent sensing against nitroaromatics (NACs) were explored. • Also, its photocatalytic properties to decompose methyl violet assessed. • Both sensing as well photocatalytic mechanism have been explained with the aid of theoretical calculations. [ABSTRACT FROM AUTHOR]

Abstract A 3D polyhedral metal organic framework, [Cu 4 (L) 2 (H 2 O) 4 ∙5DMF] n (1) (H 4 L = 3,5‑di(3,5‑dicarboxyphenyl)nitrobenzene), has been designed and successfully synthesized. 1 shows a 3D mfj topological framework with 1D triangular channels. The UV diffuse reflectance spectroscopy of the MOF indicates its semiconducting nature which induces photocatalytic property in the MOF. The photocatalytic property of 1 in photo-degradation of organic dyes viz. methyl violet and Rhodamine B have been investigated. The possible mechanism for the photocatalytic activity of 1 against organic dyes has been addressed using density of states (DOS) and partial DOS (pDOS) calculations. Graphical abstract The possible mechanism for the photocatalytic activity of 1 against organic dyes has been addressed. Unlabelled Image Highlights • The title MOF shows a 3D mfj topological framework • It exhibits photocatalytic property • The pDOS was used to confirm photocatalytic mechanism. [ABSTRACT FROM AUTHOR]

A biocompatible metal-organic framework (MOF) [Zn 2 (TPL)(FA)(OH)(H 2 O)] ( 1 ) (TPL = theophylline and H 2 FA = fumaric acid) had been chosen which offers an ideal model for the development of fluorescencent chemosensor using simple synthetic protocol. The MOF 1 have been tested as a fluorescent chemosensor against nitro-aromatics (NACs) and it displayed high selectivity for 4-NT over other NACs as evident by the emission spectroscopy. The alleviation in fluorescence intensity of 1 in presence of different NACs have been explained with the help of theoretical calculations which suggested that there is occurrence of both electron and energy transfer processes, in addition to electrostatic interaction between 1 and NACs which may be responsible for the unprecedented selective alleviation in the fluorescence intensity. Also, 1 had been deployed as a photocatalyst 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 85% photocatalytic efficiency against Rh B in 100 min, while its efficiency against MV was only 50% under the identical experimental conditions. The possible mechanism for the photocatalytic activity has been proposed using density of states (DOS) calculations. [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]

A porous Zn(II) metal–organic framework (MOF) [Zn(H 2 L)(4,4′-bipy) 0.5 ] n ( 1 ) has been selected and its luminescence sensing for cations and anions as well as the photocatalytic property against methyl violet have been explored. Luminescence studies indicated that 1 could be an efficient multifunctional fluorescent material for highly sensitive detection of metal cation Cu 2+ and anions CrO 4 2− . The luminescence intensity of 1 was found to decrease proportionately with increase in the concentration of Cu 2+ and CrO 4 2− . Furthermore, the photocatalytic property of 1 for degradation of the methyl violet (MV) have been explored and a possible photocatalytic mechanism have been proposed using density of states (DOS) and partial DOS (pDOS) calculations. [ABSTRACT FROM AUTHOR]

The hydrothermal reaction of Gd(III) salt with a new rigid dicarboxylate ligand, N , N′ ‑dioxide‑3,3′‑benzocinnoline dicarboxylic acid (H 2 L) give rise to a new metal-organic framework (MOF) {[Gd(L) 1.5 (H 2 O) 2 ]·2H 2 O} n ( 1 ). The MOF 1 shows 3D microporous framework with 1D parallelogram like channels which are constructed by single rod-shaped {Gd(CO 2 ) 2 } n chains. The thermal stability, UV/Vis diffuse-reflection spectra, magnetic properties of 1 in the temperature range 2–300 K have been explored. Also its photocatalytic property against the photo-degradation of aromatic dye Rhodamine B (Rh B) has been studied and the plausible photocatalytic mechanism has been addressed using density of states (DOS) calculations. [ABSTRACT FROM AUTHOR]

Chemodynamic therapy (CDT) regarded as a new therapeutic technique employed for treatment of tumors, by disrupting the proliferation and development of tumor cells. This is executed by activating Fenton/Fenton-like responses via endogenous chemicals by triggering severe oxidative stress, thereby achieving noninvasive treatment of deep internal tumors. Metal-organic frameworks (MOFs) are assorted subclass of coordination polymer that possess porous three-dimensional network constructed by metal ions as connecting points to bridge linkers. They could easily be functionalized and possess high porosity, and high specific surface area. It had been reported that some functionalized MOFs can disintegrate and release metal ions in the tumor microenvironment (TME) and mediate Fenton or Fenton-like reactions, catalyzing hydrogen peroxide (H 2 O 2) into hydroxyl radicals (·OH) and ultimately destroying tumor cells. In view of this, the MOFs could be functionalized appropriately to enhance CDT-triggered apoptosis and achieve anti-tumor effects. Thus, CDT strategies using MOFs to promote Fenton or Fenton-like reactions inculcate advantages of both, especially in biomedical tumor treatment, and offers great application prospects and research value. In the presented review, the latest advancements in the different MOFs finding applications in CDT are discussed and summarized. The latest advancements in the different MOFs finding applications in CDT are discussed and summarized. [Display omitted] • CDT strategies using MOFs to promote Fenton or Fenton-like reactions were discussed. • The current limitations and challenges in this field have been proposed. • The application of different MOFs for CDT are summarized. [ABSTRACT FROM AUTHOR]