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In this manuscript, we have developed an efficient spraying method to successfully fabricate a series of flower-like coordination polymers (CP) microparticles, including Co/BDC (1,4-benzenedicarboxylate) metal organic frameworks (MOF) and infinite coordination polymers (ICP) microparticles, as well as Ni-Co/BDC MOF and Zn/DOBDC (2,5-dioxido-1,4-benzenedicarboxylate) MOF. The spraying method has shown high efficiency and universality in synthesizing the flower-like CP. The crystalline structure can be adjusted by varying the solvent composition in the spraying process. SEM observation demonstrated the MOF and ICP microparticles possess the similar flower-like structure, which is composed of nanoflakes with smooth surface, and the flower-like microparticles could be monodisperse with as low as 5% polydispersity. Moreover, the fabrication of the flower-like CP microparticles by spraying has a wide operation window, because there is no need to precisely control the experiment conditions, like solvents, concentration, and spray order. Due to the practicality of spray technique, this work would pave the way for the manufacture of the flower-like materials and have great potential in applications of catalysis, sensor, energy storage, and so on., Competing Interests: The authors declare no conflict of interest. The founding sponsors had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, and in the decision to publish the results.

Five compounds, [Zn 2 (bpe)(BPTA) 2 (H 2 O) 2 ] ⋅ 2H 2 O (1); [Zn(bpe)(BPTA)] (2); [Cd(bpe)(BPTA)H 2 O] (3); [Cd(BPTA) (bpmh)] ⋅ 2H 2 O (4); and Cu 2 (BPTA) 2 (bpmh) 3 (H 2 O) 2 ] ⋅ 2H 2 O (5) were prepared employing 2,5-bis(prop-2-yn-1-yloxy)terephthalic acid (2, 5 BPTA) as the primary ligand and 1,2-di(pyridin-4-yl)ethane (4, 4' bpe) (1-3) and 1,2-bis(pyridin-3-ylmethylene)hydrazine (bpmh) (4-5) as the secondary ligands. Single crystal studies indicated that the compounds 1, 3 and 5 have two-dimensional layer structures and compounds 2 and 4 three-dimensional structures. The luminescence behaviour of the compounds 2 and 3 were explored for the sensing of metronidazole in aqueous medium. The studies indicated that the compounds can detect metronidazole in ppm level both in solution as well as simple paper strips. The Cu compound 5 was found to lose the coordinated water molecule at 100 °C without any structural change. The coordinatively unsaturated Cu-centre were examined towards the Lewis acidic character by carrying out the Ullmann type C-C homocoupling reaction of the aromatic halide compounds. The compounds, 4 and 5, also have the Lewis basic functionality arising out the =N-N=, aza groups. The bifunctional nature of the coordination polymers (CP) was explored towards the Chan-Lam coupling reaction between phenyl boronic acid and aniline derivatives in the ethanol medium. In both the catalytic reactions, good yields and recyclability were observed. The present studies illustrated the rich diversity that the transition metal containing compounds exhibit in extended framework structures., (© 2024 Wiley-VCH GmbH.)

Multifunctional drug delivery systems (DDS) are in high demand for effectively targeting specific cells, necessitating excellent biocompatibility, precise release mechanisms, and sustained release capabilities. The hollow multishelled structure (HoMS) presents a promising solution, integrating structural and compositional design for efficient DDS development amidst complex cellular environments. Herein, starting from a Fe-based metal-organic framework (MOF), amorphous coordination polymers (CP) composited HoMS with controlled shell numbers are fabricated by balancing the rate of MOF decomposition and shell formation. Fe-CP HoMS loaded with DOX is utilized for synergistic chemotherapy and chemodynamic therapy, offering excellent responsive drug release capability (excellent pH-triggered drug release 82% within 72 h at pH 5.0 solution with doxorubicin (DOX) loading capacity of 284 mg g -1 ). In addition to its potent chemotherapy attributes, Fe-CP-HoMS possesses chemodynamic therapy potential by continuously catalyzing H 2 O 2 to generate ·OH species within cancer cells, thus effectively inhibiting cancer cell proliferation. DOX@3S-Fe-CP-HoMS, at a concentration of 12.5 µg mL -1 , demonstrates significant inhibitory effects on cancer cells while maintaining minimal cytotoxicity toward normal cells. It is envisioned that CP-HoMS could serve as an effective and biocompatible platform for the advancement of intelligent drug delivery systems in the realm of cancer therapy., (© 2024 Wiley‐VCH GmbH.)

Lead halide hybrids have shown great potentials in CO 2 photoreduction, but challenging to afford C 2+ reduced products, especially using H 2 O as the reductant. This is largely due to the trade-off problem between instability of the benchmark 3D structures and low carrier mobility of quasi-2D analogues. Herein, the lead halide dimensionality of robust coordination polymers (CP) was modulated by organic ligands differing in a single-atom change (NH vs. CH 2 ), in which the NH groups coordinate with interlamellar [PbI 2 ] clusters to achieve the important 2D→3D transition. This first CP based on 3D cationic lead iodide sublattice possesses both high aqueous stability and a low exciton binding energy of 25 meV that is on the level of ambient thermal energy, achieving artificial photosynthesis of C 2 H 5 OH. Photophysical studies combined with theoretical calculations suggest the bridging [PbI 2 ] clusters in the 3D structure not only results in enhanced carrier transport, but also promotes the intrinsic charge polarization to facilitate the C-C coupling. With trace loading of Rh cocatalyst, the apparent quantum efficiency of the 3D CP reaches 1.4 % at 400 nm with a high C 2 H 5 OH selectivity of 89.4 % (product basis), which presents one of the best photocatalysts for C 2 products to date., (© 2024 Wiley‐VCH GmbH.)

A new class of lanthanide mixed-carboxylate ligands compounds with formula {[Ln 2 (phthgly) 4 (bdc)(H 2 O) 6 ]·(H 2 O) 4 } ∞ , labelled as Ln 3+ : Eu (1) and Gd (2) coordination polymers (CP) were synthesized under mild reaction conditions between lanthanide nitrate salts and a solution of N-phthaloylglycine (phthgly) and terephthalic (bdc) ligands. The (1) and (2) coordination polymers were formed by symmetric binuclear units, in which phthgly and bdc carboxylate ligands are coordinated to the lanthanide ions by different coordination modes. Surprisingly, all organic ligands participate in hydrogen bonding interactions, forming an extremally rigid crystalline structure. The red narrow emission bands from the 5 D 0 → 7 F J transitions of the Eu 3+ ion show a high colour purity. The intramolecular energy transfer process from L→Eu 3+ ion has been discussed. The experimental intensity parameters (Ω 2,4 ) reflect lower angular distortion and polarizability of the chemical environment around the metal ion compared with other Eu 3+ compounds reported in the literature. This novel class of coordination polymer offers a more attractive platform for developing luminescent functional materials for different applications., (© 2023 John Wiley & Sons Ltd.)

Bismuth metal-organic frameworks and coordination polymers (CP) are challenging to synthesize, given the poor solubility of bismuth precursors and asymmetric and labile ligation of Bi 3+ due to its intrinsic lone pair. Here, we synthesize and structurally characterize three Bi 3+ -CPs, exploiting a tetrafluoroterephtalate (F 4 BDC) linker to determine the effect of high acidity on these synthesis and coordination challenges. Single-crystal X-ray diffraction characterization showed that pi-pi stacking of linkers directs framework arrangement and generally deters open porosity in the three structures, respectively featuring Bi chains ( Bi chain -F 4 BDC ), Bi dimers ( Bi 2 -F 4 BDC ) linked into chains, and Bi tetramers ( Bi 4 -F 4 BDC ). Powder X-ray diffraction and microscopic imaging show the high purity and stability of these compounds in water. Naphthalenedisulfonate (NDS) was used as a mineralizer in the synthesis of ( Bi chain -F 4 BDC ) and ( Bi 4 -F 4 BDC ), and studies of its role in assembly pathways yielded two additional structures featuring mixed NDS and F 4 BDC, respectively, linking monomer and octamer Bi nodes, and confirmed that F 4 BDC is the preferred (less labile) linker. Methylene blue (MB) adsorption studies show differing efficacies of the three Bi-F 4 BDC phases, attributed to surface characteristics of the preferential growth facets, while generally most effective adsorption is attributed to the hydrophobicity of fluorinated ligands. Finally, thermogravimetric analysis of all three Bi-F 4 BDC phases indicates simultaneous ligand degradation and in situ formation of volatile Bi compounds, which could be exploited in the chemical vapor deposition of Bi-containing thin films., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

A systematic chain length variation of the ligand para -MeOC 6 H 4 S(CH 2 ) m SC 6 H 4 OMe (1 ≤ m ≤ 8) was performed to study its effect on the structures and photophysical properties of the coordination polymers (CP) when reacted with CuI. Indeed, direct correlations are noted between these features and m . When m is an odd number, the secondary building unit is systematically the common closed-cubane Cu 4 I 4 cluster, rendering the material strongly luminescent ( i.e. , emission quantum yield, Φ e > 20%), and the CP is one-dimensional (1D). However, when m is 2, 4, and 6, the SBUs exhibit rare polymeric motifs of (Cu 2 I 2 ) n : staircase ribbon, fused poly(rhombic pseudo-dodecahedron), and accordion ribbon, respectively, and the emission intensities are either very weak (Φ e < 0.001%) or of medium intensity (Φ e ∼ 10% when m = 6). When m = 8 ( i.e . the most flexible chain), the SBU is a closed-cubane Cu 4 I 4 and the emission intensity is medium (Φ e ∼ 10%). A special case was observed for m = 3, where a co-crystallization of the molecular cluster Cu 4 I 4 (NCCH 3 ) 4 is observed in the lattice, which turns out to be quite important for the stability of the network.

Due to remarkable fluorescence characteristics, lanthanide coordination polymers (CP) have been widely employed in fluorescence detection, but it is rarely reported that they act as multifunctional luminescent probes dedicated to detecting malachite green (MG) and various metal ions. A europium-based CP fluorescent probe, Eu(PDCA) 2 (H 2 O) 6 (PDCA = 2,6-pyridinedicarboxylic acid), has been synthesized and exhibited excellent recognition ability for malachite green and metal cations (Cr 3+ , Fe 3+ and Cu 2+ ) among 11 metal cations, 13 anions and six other compounds. The recognition was achieved by fluorescence quenching when MG, Cr 3+ , Fe 3+ and Cu 2+ were added to a suspension of Eu(PDCA) 2 (H 2 O) 6 respectively. Eu(PDCA) 2 (H 2 O) 6 is a multifunctional luminescent probe, and displayed high quenching efficiencies K sv (2.10 × 10 6 M -1 for MG; 1.46 × 10 5 M -1 for Cr 3+ ; 7.26 × 10 5 M -1 for Fe 3+ ; 3.64 × 10 5 M -1 for Cu 2+ ), and low detection limits (MG: 0.039 μM; Cr 3+ : 0.539 μM; Fe 3+ : 0.490 μM; Cu 2+ : 0.654 μM), presenting excellent selectivity and sensitivity, especially for MG. In addition, Eu(PDCA) 2 (H 2 O) 6 was also made into fluorescent test strips, which can rapidly and effectively examine trace amounts of MG, Cr 3+ , Fe 3+ and Cu 2+ in aqueous solutions. This work provides a new perspective for detecting malachite green in fish ponds and heavy metal ions in waste water., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Metal-organic coordination polymers (CP) have attracted the scientific attention for electrochemical water oxidation as it has the similar coordination structure like natural photosynthetic coordinated complex. However, the harsh synthesis conditions and bulky nature pose a major challenge in the field of catalysis. Herein, 3-5 nm CP particles synthesized at room temperature using aqueous solutions of Ni 2+ /Cu 2+ and 2,5-dihydroxyterepthalic acid as precursor were applied for alkaline water and urea electrolysis. The overpotential required is only 300 mV at 10 mA cm -2 by Nano-Ni CP for water oxidation, with turnover frequency (TOF) of 21.4 s -1 which is around 8 times higher than its bulk-counterpart. Overall water and urea splitting were achieved with Nano-Cu (-) ∥ Nano-Ni (+) couple on Ni foam at 1.69 and 1.52 V to achieve 10 mA cm -2 , respectively. High electrochemical surface area (ECSA), high TOF, and enhanced mass diffusion are found to be the key parameters responsible for the state-of-the-art water and urea splitting performances of nano-CPs as compared to their bulk counterparts., (© 2021 Wiley-VCH GmbH.)

Photoluminescence (PL) intensity in organic or metal-organic emitters usually suffers from thermal quenching (TQ), which severely hinders their industrial applications. The development of negative thermal quenching (NTQ) and/or zero thermal quenching (ZTQ) materials depends on a better understanding of the mechanisms underpinning TQ in luminescent solids. In this work, we investigated the temperature dependence of thermally activated delayed fluorescence (TADF) in copper(I)-organic coordination polymers (CP) ligated with an imidazole or triazole derivative over a broad temperature range. The efficient PL emission of CP1 is heavily quenched as the crystalline samples are cooled to 77 K; the PL intensity shows the NTQ effect in the region of 77-238 K followed by a ZTQ effect in the temperature range of 238-318 K. No NTQ or ZTQ effect is observed for reference coordination polymer CP2 , where the 1,2,4-triazole group was used instead of the imidazole one. Our work highlights the important role of the ligand's electronic structure in optimizing photophysical properties of coordination polymer emitters and may stimulate new efforts to design luminescent materials exhibiting NTQ and ZTQ effect at higher temperature.

The isocarbonyl-ligated metallocene coordination polymers [Cp* 2 M(μ-OC)W(Cp)(CO)(μ-CO)] ∞ were synthesized with M = Gd ( 1 , L = THF) and Dy ( 2 , no L). In a zero direct-current field, the dysprosium version 2 was found to be a single-molecule magnet (SMM), with analysis of the dynamic magnetic susceptibility data revealing that the axial metallocene coordination environment leads to a large anisotropy barrier of 557(18) cm -1 and a fast quantum-tunnelling rate of ∼3.7 ms. Theoretical analysis of two truncated versions of 2 , [Cp* 2 Dy{(μ-OC)W(Cp)(CO) 2 } 2 ] - ( 2a ), and [Cp* 2 Dy(OC) 2 ] + ( 2b ), in which the effects of electron correlation outside the 4f orbital space were studied, revealed that tungsten-to-carbonyl back-donation plays an important role in determining the strength of the competing equatorial field at dysprosium and, hence, the dynamic magnetic properties. The finding that a classical organo-transition-metal bonding scenario can be used as an indirect way of tuning the rate of quantum tunnelling potentially provides an alternative chemical strategy for utilizing the fast magnetic relaxation properties of SMMs.

The reactions of tetrahedral molybdenum complexes bearing unsubstituted heterodiatomic Group 15 elements, [Cp 2 Mo 2 (CO) 4 (μ,η 2 :η 2 -PE)] (Cp=C 5 H 5 ; E=As (1), Sb (2)), with Cu I halides afforded seven unprecedented neutral supramolecular assemblies. Depending on the Mo 2 PE units and the Cu I halide, the oligomers [⟨{Cp 2 Mo 2 (CO) 4 }{μ 4 ,η 2 :η 2 :η 2 :η 1 -PE}⟩ 4 ⟨{CuX}{Cu(μ-X)}⟩ 2 ] (E=As (X=Cl (3), Br (4)); E=Sb (X=Cl (6), Br (7))) or the 1D coordination polymers [{Cp 2 Mo 2 (CO) 4 }{μ 4 ,η 2 :η 2 :η 1 :η 1 -PAs}{Cu(μ-I)}] n (5) and [{Cp 2 Mo 2 (CO) 4 }{μ 4 ,η 2 :η 2 :η 2 :η 1 -PSb} 2 {Cu(μ-X)} 3 ] n (X=I (8), Br (9)) are accessible. These solid-state aggregates are the first and only examples featuring the organometallic heterodiatomic Mo 2 PE complexes 1 and 2 as linking moieties. DFT calculations demonstrate that complexes 1 and 2 present a unique class of mixed-donor ligands coordinating to Cu I centers via the P lone pair and the P-E σ-bond, revealing an unprecedented coordination mode., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Metal-organic frameworks (MOFs) are porous coordination polymers (CP) produced by metal-based nodes and multitopic organic ligands. Based on their porous and microcrystalline powder structures, they have initially been used for storage, catalysis and separation. Then, because of their advantageous properties like ease of the tailoring, they also have been applied in areas like chemical sensing, biological applications, etc. The CPs were combined with molecules such as organic dyes, small biomolecules, nanomaterials like nanoparticles, nanowires, nanofibers and polymers and as a result, composite MOFs have been produced. By this way, better mechanical stability, conductivity, and catalytic performance were obtained. This review (with 135 refs.) summarizes the progress made in the past years in the field of electrochemical and optical sensing based on the use of MOFs. Following an introduction into the field, large sections cover MOF based sensors exploiting (a) carbon nanomaterials (with subsections on carbon nanotubes, graphene and its derivatives), (b) metal/metal oxide MOFs; including gold, silver, copper and/or copper oxide nanoparticle and other metal/MOF composites. Enzyme mimicking MOFs are discussed next. In this context, after the brief information about focused MOFs, the nanomaterial/MOF composites were discussed and related examples were presented. Graphical abstract MOF structures in Sensing Systems.

Highly pure semiconducting single-walled carbon nanotubes (SWNTs) are essential for the next generation of electronic devices, such as field-effect transistors and photovoltaic applications; however, contamination by metallic SWNTs reduces the efficiency of their associated devices. Here we report a simple and efficient method for the separation of semiconducting- and metallic SWNTs based on supramolecular complex chemistry. We here describe the synthesis of metal-coordination polymers (CP-Ms) composed of a fluorene-bridged bis-phenanthroline ligand and metal ions. On the basis of a difference in the 'solubility product' of CP-M-solubilized semiconducting SWNTs and metallic SWNTs, we readily separated semiconducting SWNTs. Furthermore, the CP-M polymers on the SWNTs were simply removed by adding a protic acid and inducing depolymerization to the monomer components. We also describe molecular mechanics calculations to reveal the difference of binding and wrapping mode between CP-M/semiconducting SWNTs and CP-M/metallic SWNTs. This study opens a new stage for the use of such highly pure semiconducting SWNTs in many possible applications.

A classical molecular mechanics force field, able to simulate coordination polymers (CP) based on ruthenium carboxylates (Ru2 (O2CReq )4 Lax) (eq = equatorial group containing aliphatic chains, Lax = axial ligand), has been developed. New parameters extracted from experimental data and quantum calculations on short aliphatic chains model systems were included in the generalized AMBER force field. The proposed parametrization was evaluated using model systems with known structure, containing either short or long aliphatic chains; experimental results were reproduced satisfactorily. This modified force field, although in a preliminary stage, could then be applied to long chain liquid crystalline compounds. The resulting atomistic simulations allowed assessing the relative influence of the factors determining the CP conformation, determinant for the physical properties of these materials., (Copyright © 2013 Wiley Periodicals, Inc.)

A new class of infinite coordination polymers (CP) was synthesized using a tetrahedral tetrakis[4-(4'-phenyl-2,2':6',2''-terpyridine)phenyl]methane ligand as an organic node to direct the three-dimensional growth of the network and M(II) (M = Zn, Fe, Ni, and Ru) ions as inorganic linkers, an approach that is the opposite of the metal-as-a-node strategy used in the construction of metal-organic frameworks (MOFs). The unusual rod-like morphology of the resulting microporous materials can be tuned via solvents and reaction conditions. The covalent entrapment of a [Ru(tpy)(2)](2+) moiety in the skeleton of the 3D-network enables the Ru-CP to exhibit room-temperature luminescence., (This journal is © The Royal Society of Chemistry 2011)