scholarly journals Metal-organic magnets with large coercivity and ordering temperatures up to 242°C

Science ◽  
2020 ◽  
Vol 370 (6516) ◽  
pp. 587-592 ◽  
Author(s):  
Panagiota Perlepe ◽  
Itziar Oyarzabal ◽  
Aaron Mailman ◽  
Morgane Yquel ◽  
Mikhail Platunov ◽  
...  
Keyword(s):  
Metal Ions ◽  
Room Temperature ◽  
Building Blocks ◽  
Inorganic Materials ◽  
Coordination Networks ◽  
Critical Temperatures ◽  
Considerable Success ◽  
Organic Magnets ◽  
Metal Organic ◽  
Constituent Elements

Magnets derived from inorganic materials (e.g., oxides, rare-earth–based, and intermetallic compounds) are key components of modern technological applications. Despite considerable success in a broad range of applications, these inorganic magnets suffer several drawbacks, including energetically expensive fabrication, limited availability of certain constituent elements, high density, and poor scope for chemical tunability. A promising design strategy for next-generation magnets relies on the versatile coordination chemistry of abundant metal ions and inexpensive organic ligands. Following this approach, we report the general, simple, and efficient synthesis of lightweight, molecule-based magnets by postsynthetic reduction of preassembled coordination networks that incorporate chromium metal ions and pyrazine building blocks. The resulting metal-organic ferrimagnets feature critical temperatures up to 242°C and a 7500-oersted room-temperature coercivity.

Evolution of tubular copper sulfide nanostructures from copper(i)–metal organic precursor: a superior platform for the removal of Hg(ii) and Pb(ii) ions

RSC Advances ◽  
2015 ◽  
Vol 5 (16) ◽  
pp. 12446-12453 ◽  
Author(s):  
Chaiti Ray ◽  
Sougata Sarkar ◽  
Soumen Dutta ◽  
Anindita Roy ◽  
Ramkrishna Sahoo ◽  
...  
Keyword(s):  
Heavy Metal ◽  
Metal Ions ◽  
Copper Sulfide ◽  
Heavy Metal Ions ◽  
Room Temperature ◽  
Mixed Phase ◽  
Organic Precursor ◽  
Metal Organic

Room temperature synthesized porous mixed phase copper sulfide acts as an effective adsorbent for the removal of heavy metal ions from water.

scholarly journals Semiconductors and Aperiodic Structures in Organocyanide-Based Materials

2014 ◽  
Vol 70 (a1) ◽  
pp. C1265-C1265
Author(s):  
Xuan Zhang ◽  
Hanhua Zhao ◽  
Lukas Palatinus ◽  
Kevin Gagnon ◽  
John Bacsa ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Metal Ions ◽  
Building Blocks ◽  
Inorganic Materials ◽  
Water Molecules ◽  
High Symmetry ◽  
Temperature Conductivity ◽  
Room Temperature Conductivity ◽  
Space Group ◽  
Π Stacking

Organocyanides such as TCNQ (tetracyanoquinodimethane) and DCNQI (dicyanoquinodiimine) are excellent electron acceptors and have been extensively studied in electrically conducting/switching and magnetic materials. Supramolecular interactions such as π-stacking and hydrogen bonding in addition to coordination bonds with metal ions play an important role in the self-assembly of these functional inorganic materials. A novel semiconductor Cd2(TCNQ)3.5(H2O)2 with non-integer valences of TCNQ was synthesized and is the first example that exhibits four bridging modes of TCNQ in one structure (Figure 1). Despite the rather large stacking distance of 3.687(1) Å between the two μ3-TCNQ species, which constitute a "broken link" in the electron conducting pathway, the semiconductor exhibits a room temperature conductivity of 5.8×10-3 S·cm-1. The hydrogen bonding interactions between the coordinated water molecules and nitrogen atoms of the mu2- and mu3-TCNQ help to stabilize these coordinatively unsaturated TCNQ species. Another application of the chemistry of organocyanides in the context of this research is the study of reactions of the meta-dicyanamidobenzene dianion (DCYD2-) which was predicted by Ruiz and coworkers to facilitate ferromagnetic interactions between certain paramagnetic metal ions. The DCYD2- anion self-assembles with Mn(II) building blocks to afford a rare example of inorganic quadruple helices with an incommensurate modulated structure (Figure 2a). A supercell in the high symmetry space group P4/nnc is obtained with a c parameter five times that of the basic structure and a further 15-fold expansion in the space group of P1 along the c axis reveals that ~2% of Mn positions are disordered. The packing of these helical chains through π-stacking of pyridyl groups leads to 1D nanochannels with an estimated empty volume of 38.6% of the super cell volume (31,587Å3). However, in the presence of water, hydrogen bonding between the water molecules and the cyano-N atoms dominates and only zig-zag chains are formed (Figure 2b).

Combinatorial Peptide Libraries for Selecting Inorganic-Binding Proteins: A Step in Molecular Biomimetics

2003 ◽  
Vol 773 ◽  
Author(s):  
C. Tamerler ◽  
S. Dinçer ◽  
D. Heidel ◽  
N. Karagûler ◽  
M. Sarikaya
Keyword(s):  
Binding Proteins ◽  
Building Blocks ◽  
Molecular Engineering ◽  
Inorganic Materials ◽  
Combinatorial Peptide Libraries ◽  
Self Assembling ◽  
Complex Functions ◽  
Recent Developments ◽  
Specific Proteins ◽  
Molecular Biomimetics

AbstractProteins, one of the building blocks in organisms, not only control the assembly in biological systems but also provide most of their complex functions. It may be possible to assemble materials for practical technological applications utilizing the unique advantages provided by proteins. Here we discuss molecular biomimetic pathways in the quest for imitating biology at the molecular scale via protein engineering. We use combinatorial biology protocols to select short polypeptides that have affinity to inorganic materials and use them in assembling novel hybrid materials. We give an overview of some of the recent developments of molecular engineering towards this goal. Inorganic surface specific proteins were identified by using cell surface and phage display technologies. Examples of metal and metal oxide specific polypeptides were represented with an emphasis on certain level of specificities. The recognition and self assembling characteristics of these inorganic-binding proteins would be employed in develeopment of hybrid multifunctional materials for novel bio- and nano-technological applications.

A Series of Metal-Organic Frameworks for Selective CO2 Capture and Catalytic Oxidative Carboxylation of Olefins

2018 ◽  
Author(s):  
Huong T. D. Nguyen ◽  
Y B. N. Tran ◽  
Hung N. Nguyen ◽  
Tranh C. Nguyen ◽  
Felipe Gándara ◽  
...  
Keyword(s):  
Room Temperature ◽  
Gas Adsorption ◽  
New Materials ◽  
One Pot ◽  
Acid Gas ◽  
Naphthalene Diimide ◽  
Styrene Carbonate ◽  
Metal Organic ◽  
Adsorption Of Co ◽  
The One

<p>Three novel lanthanide metal˗organic frameworks (Ln-MOFs), namely MOF-590, -591, and -592 were constructed from a naphthalene diimide tetracarboxylic acid. Gas adsorption measurements of MOF-591 and -592 revealed good adsorption of CO<sub>2</sub> (low pressure, at room temperature) and moderate CO<sub>2</sub> selectivity over N<sub>2</sub> and CH<sub>4</sub>. Accordingly, breakthrough measurements were performed on a representative MOF-592, in which the separation of CO<sub>2</sub> from binary mixture containing N<sub>2</sub> and CO<sub>2</sub> was demonstrated without any loss in performance over three consecutive cycles. Moreover, MOF-590, MOF-591, and MOF-592 exhibited catalytic activity in the one-pot synthesis of styrene carbonate from styrene and CO<sub>2</sub> under mild conditions (1 atm CO<sub>2</sub>, 80 °C, and solvent-free). Among the new materials, MOF-590 revealed a remarkable efficiency with exceptional conversion (96%), selectivity (95%), and yield (91%). </p><br>

A Highly Crystalline Anthracene-Based MOF-74 Series Featuring Electrical Conductivity and Luminescence

2019 ◽  
Author(s):  
Patricia Scheurle ◽  
Andre Mähringer ◽  
Andreas Jakowetz ◽  
Pouya Hosseini ◽  
Alexander Richter ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Metal Ions ◽  
Light Emission ◽  
Block Design ◽  
High Surface ◽  
Visible Spectrum ◽  
Building Blocks ◽  
Divalent Metal Ions ◽  
Conductivity Enhancement ◽  
Surface Areas

Recently, a small group of metal-organic frameworks (MOFs) has been discovered featuring substantial charge transport properties and electrical conductivity, hence promising to broaden the scope of potential MOF applications in fields such as batteries, fuel cells and supercapacitors. In combination with light emission, electroactive MOFs are intriguing candidates for chemical sensing and optoelectronic applications. Here, we incorporated anthracene-based building blocks into the MOF-74 topology with five different divalent metal ions, that is, Zn2+, Mg2+, Ni2+, Co2+ and Mn2+, resulting in a series of highly crystalline MOFs, coined ANMOF-74(M). This series of MOFs features substantial photoluminescence, with ANMOF-74(Zn) emitting across the whole visible spectrum. The materials moreover combine this photoluminescence with high surface areas and electrical conductivity. Compared to the original MOF-74 materials constructed from 2,5-dihydroxy terephthalic acid and the same metal ions Zn2+, Mg2+, Ni2+, Co2+ and Mn2+, we observed a conductivity enhancement of up to six orders of magnitude. Our results point towards the importance of building block design and the careful choice of the embedded MOF topology for obtaining materials with desired properties such as photoluminescence and electrical conductivity.

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.

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