One, two, and three-dimensional metal–organic coordination polymers derived from enantiopure organic phosphorate: homochirality, water stability and proton conduction

CrystEngComm ◽  
2017 ◽  
Vol 19 (42) ◽  
pp. 6325-6332 ◽  
Author(s):  
Xiaoqiang Liang ◽  
Kun Cai ◽  
Feng Zhang ◽  
Jia Liu ◽  
Guangshan Zhu
Keyword(s):  
Activation Energy ◽  
Metal Ions ◽  
Coordination Polymers ◽  
Three Dimensional ◽  
High Water ◽  
Water Stability ◽  
Lower Activation ◽  
Metal Organic ◽  
Lower Activation Energy ◽  
Multifunctional Ligand

A multifunctional ligand reacts with metal ions to generate three new coordination polymers, where 3 has a high water stability, a moderate proton conductivity and a lower activation energy.

scholarly journals Lower Activation Energy for Catalytic Reactions through Host-Guest Cooperation within Metal-Organic Frameworks

2018 ◽  
Vol 130 (32) ◽  
pp. 10264-10268 ◽  
Author(s):  
Briana Aguila ◽  
Qi Sun ◽  
Xiaoliang Wang ◽  
Erica O'Rourke ◽  
Abdullah M. Al-Enizi ◽  
...  
Keyword(s):  
Activation Energy ◽  
Metal Organic Frameworks ◽  
Catalytic Reactions ◽  
Lower Activation ◽  
Metal Organic ◽  
Lower Activation Energy

scholarly journals Lower Activation Energy for Catalytic Reactions through Host-Guest Cooperation within Metal-Organic Frameworks

2018 ◽  
Vol 57 (32) ◽  
pp. 10107-10111 ◽  
Author(s):  
Briana Aguila ◽  
Qi Sun ◽  
Xiaoliang Wang ◽  
Erica O'Rourke ◽  
Abdullah M. Al-Enizi ◽  
...  
Keyword(s):  
Activation Energy ◽  
Metal Organic Frameworks ◽  
Catalytic Reactions ◽  
Lower Activation ◽  
Metal Organic ◽  
Lower Activation Energy

Syntheses, Photoluminescent Properties, and Structural Investigation of Five Complexes based on a New T-Shaped 2-(Pyridin-3-yl)-4,6-Pyrimidine Dicarboxylic Acid Ligand: Structure Evolution from One-dimensional Chains to Three-dimensional Architectures

2013 ◽  
Vol 66 (11) ◽  
pp. 1342 ◽  
Author(s):  
Dongsheng Deng ◽  
Guohui Kang ◽  
Baoming Ji ◽  
Hongliang Li ◽  
Guirong Qu ◽  
...  
Keyword(s):  
Metal Ions ◽  
Dicarboxylic Acid ◽  
Coordination Polymers ◽  
Metal Organic Framework ◽  
Three Dimensional ◽  
Three Dimensions ◽  
Structure Evolution ◽  
Hydrothermal Conditions ◽  
Metal Organic ◽  
Organic Framework

A series of structurally diverse coordination polymers, [Mn(ppmdc)(H2O)2]n (1), [Cu(ppmdc)(H2O)2]n (2), {[Co(ppmdc)][Co(ppmdc)(H2O)]}n (3), [Zn(ppmdc)(H2O)]n (4), and [Cd(ppmdc)]n (5) (H2ppmdc = 2-(pyridin-3-yl)-4,6-pyrimidine dicarboxylic acid) were obtained from metal salts and H2ppmdc under hydrothermal conditions. Single crystal X-ray structural analysis reveals that complexes 1–5 have different structures, ranging from one- to three-dimensions, which are mainly due to the different metal ions, and especially the coordination mode of the H2ppmdc ligand. Complexes 1 and 2 are 1D coordination polymers, in which the ppmdc2– ligand adopts a bis-(bidentate) mode to link metal ions. Complexes 3 and 4 feature a 2D metal-organic framework with Schläfli topologies of (4.62) (42.62.82) and (4.82), respectively, in which the metal ions are bridged by μ3-ppmdc2– ligands. Complex 5 possesses a 3D nanotubular metal-organic framework with a point symbol of (49.66) topology built up from the 6-connected ppmdc2– ligands and Cd(ii) ions. The thermal properties of complexes 1–5 have been determined. Moreover, investigation of photoluminescent properties reveals that the configuration of ppmdc2– resulting from metal-directed coordination has a profound effect on the fluorescence emissions of complexes 4 and 5.

scholarly journals Synthesis of a metal–organic framework by plasma in liquid to increase reduced metal ions and enhance water stability

RSC Advances ◽  
2021 ◽  
Vol 11 (37) ◽  
pp. 22756-22760
Author(s):  
Moriyuki Kanno ◽  
Takashi Kitao ◽  
Tsuyohito Ito ◽  
Kazuo Terashima
Keyword(s):  
Metal Ions ◽  
Metal Organic Framework ◽  
High Water ◽  
Water Stability ◽  
Metal Organic ◽  
Organic Framework ◽  
Plasma In Liquid

Plasma in liquid provides a method for the synthesis of HKUST-1 with increased reduced metal ions and high water stability.

Metal-organic Nanopharmaceuticals

2020 ◽  
Vol 8 (3) ◽  
pp. 163-190
Author(s):  
Benjamin Steinborn ◽  
Ulrich Lächelt
Keyword(s):  
Metal Ions ◽  
Coordination Polymers ◽  
Active Agent ◽  
Lewis Base ◽  
High Loading ◽  
Active Components ◽  
Base Functions ◽  
Metal Organic ◽  
Theranostic Applications ◽  
Pharmacologically Active

: Coordinative interactions between multivalent metal ions and drug derivatives with Lewis base functions give rise to nanoscale coordination polymers (NCPs) as delivery systems. As the pharmacologically active agent constitutes a main building block of the nanomaterial, the resulting drug loadings are typically very high. By additionally selecting metal ions with favorable pharmacological or physicochemical properties, the obtained NCPs are predominantly composed of active components which serve individual purposes, such as pharmacotherapy, photosensitization, multimodal imaging, chemodynamic therapy or radiosensitization. By this approach, the assembly of drug molecules into NCPs modulates pharmacokinetics, combines pharmacological drug action with specific characteristics of metal components and provides a strategy to generate tailorable multifunctional nanoparticles. This article reviews different applications and recent examples of such highly functional nanopharmaceuticals with a high ‘material economy’. : Lay Summary: Nanoparticles, that are small enough to circulate in the bloodstream and can carry cargo molecules, such as drugs, imaging or contrast agents, are attractive materials for pharmaceutical applications. A high loading capacity is a generally aspired parameter of nanopharmaceuticals to minimize patient exposure to unnecessary nanomaterial. Pharmaceutical agents containing Lewis base functions in their molecular structure can directly be assembled into metal-organic nanopharmaceuticals by coordinative interaction with metal ions. Such coordination polymers generally feature extraordinarily high loading capacities and the flexibility to encapsulate different agents for a simultaneous delivery in combination therapy or ‘theranostic’ applications.

scholarly journals Development of a PtSn bimetallic catalyst for direct fuel cells using bio-butanol fuel

2015 ◽  
Vol 51 (69) ◽  
pp. 13412-13415 ◽  
Author(s):  
V. K. Puthiyapura ◽  
D. J. L. Brett ◽  
A. E. Russell ◽  
W. F. Lin ◽  
C. Hardacre
Keyword(s):  
Activation Energy ◽  
Fuel Cells ◽  
Bimetallic Catalyst ◽  
Lower Activation ◽  
Lower Activation Energy

PtSn showed a higher activity and lower activation energy towards butanol electrooxidation compared to pure Pt.

Syntheses, structures and characterization of isomorphous CoII and NiII coordination polymers based on 2-[(1H-imidazol-1-yl)methyl]-6-methyl-1H-benzimidazole and benzene-1,4-dicarboxylate

2017 ◽  
Vol 73 (8) ◽  
pp. 645-651 ◽  
Author(s):  
Qiu-Ying Huang ◽  
Yang Zhao ◽  
Xiang-Ru Meng
Keyword(s):  
Coordination Polymers ◽  
Rational Design ◽  
Three Dimensional ◽  
Spectroscopic Properties ◽  
Polymeric Chain ◽  
Design And Synthesis ◽  
Carboxylate Groups ◽  
Metal Organic ◽  
The One ◽  
Ir Spectroscopic

Careful choice of the organic ligands is one of the most important parameters in the rational design and synthesis of coordination polymers. Aromatic polycarboxylates have been widely used in the preparation of metal–organic polymers since they can utilize various coordination modes to form diverse structures and can act as hydrogen-bond acceptors and donors in the assembly of supramolecular structures. Nitrogen-heterocyclic organic compounds have also been used extensively as ligands for the construction of polymers with interesting structures. In the polymers catena-poly[[[diaquabis{2-[(1H-imidazol-1-yl)methyl]-6-methyl-1H-benzimidazole-κN 3}cobalt(II)]-μ2-benzene-1,4-dicarboxylato-κ2 O 1:O 4] dihydrate], {[Co(C8H4O4)(C12H11N4)2(H2O)2]·2H2O} n , (I), and catena-poly[[[diaquabis{2-[(1H-imidazol-1-yl)methyl]-6-methyl-1H-benzimidazole-κN 3}nickel(II)]-μ2-benzene-1,4-dicarboxylato-κ2 O 1:O 4] dihydrate], {[Ni(C8H4O4)(C12H11N4)2(H2O)2]·2H2O} n , (II), the CoII or NiII ion lies on an inversion centre and exhibits a slightly distorted octahedral coordination geometry, coordinated by two N atoms from two imidazole rings and four O atoms from two monodentate carboxylate groups and two water molecules. The dicarboxylate ligands bridge metal ions forming a polymeric chain. The 2-[(1H-imidazol-1-yl)methyl]-6-methyl-1H-benzimidazole ligands coordinate to the CoII or NiII centres in monodentate modes through an imidazole N atom and are pendant on opposite sides of the main chain. The two structures are isomorphous. In the crystal, the one-dimensional chains are further connected through O—H...O, O—H...N and N—H...O hydrogen bonds, leading to a three-dimensional supramolecular architecture. In addition, the IR spectroscopic properties, PXRD patterns, thermogravimetric behaviours and fluorescence properties of both polymers have been investigated.

Enhanced water stability and high CO2 storage capacity of Lewis basic sites containing zirconium metal–organic framework

2021 ◽  
Author(s):  
Selcuk Demir ◽  
Nuray Bilgin ◽  
H. Merve Cepni ◽  
Hiroyasu Furukawa ◽  
Fatih Yilmaz ◽  
...  
Keyword(s):  
Metal Ions ◽  
Storage Capacity ◽  
Metal Organic Framework ◽  
Co2 Storage ◽  
Metal Organic Frameworks ◽  
Water Stability ◽  
High Co2 ◽  
Metal Organic ◽  
Zirconium Metal ◽  
Selection Of

Metal–organic frameworks (MOFs) are an emerging class of materials employed for custom-designed purposes by judicious selection of the linker and the metal ions. Among the MOFs composed of carboxylate linkers,...

The diffusion of Fe2+ ions in spinels with relevance to the process of maghemitization

1980 ◽  
Vol 43 (331) ◽  
pp. 889-899 ◽  
Author(s):  
W. Freer ◽  
R. O'Reilly
Keyword(s):  
Activation Energy ◽  
Spinel Structure ◽  
Single Phase ◽  
Sea Water ◽  
Magnetic Minerals ◽  
Magnetic Studies ◽  
Water Leaching ◽  
Lower Activation ◽  
Diffusion Activation ◽  
Lower Activation Energy

SummaryThe maghemitization process, by which magnetic minerals with spinel structure become progressively oxidized but remain single phase spinels, seems to be an important feature of submarine weathering. Whether the process takes place by the minerals acquiring oxygen from the sea-water or by the sea-water leaching out iron, the controlling process is the diffusion of Fe2+ in the spinel structure. Magnetic studies have suggested that during maghemitization the availability for oxidation of Fe2+ in the tetrahedral (A) sites of the spinel structure is much less than that in octahedral (B) sites. In this study the Fe2+-containing spinels FeAl2O4, FeCr2O4, FeGa2O4, and Fe2GeO4, in which Fe2+ is predominantly in either A or B sites were prepared, and the diffusion of Fe2+ was studied by (1) interdiffusion experiments with the Mg2+ counterparts and (2) oxidation experiments in air. Fe2GeO4 (Fe2+ in B sites) was found to be associated with a higher interdiffusion coefficient and lower activation energy than FeAl2O4 (75% Fe2+ in A sites). Oxidation/diffusion activation energies of 0.27 and 0.71 eV were assigned to Fe2+ in B and A sites respectively. The experiments thus provide support for the maghemitization model in which Fe2+ in B sites is preferentially oxidized.

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