Superexchange Charge Transport in Loaded Metal Organic Frameworks

ACS Nano ◽  
2016 ◽  
Vol 10 (7) ◽  
pp. 7085-7093 ◽  
Author(s):  
Tobias Neumann ◽  
Jianxi Liu ◽  
Tobias Wächter ◽  
Pascal Friederich ◽  
Franz Symalla ◽  
...  
Keyword(s):  
Charge Transport ◽  
Metal Organic Frameworks ◽  
Metal Organic

Magnetic Ordering via Itinerant Ferromagnetism in a Metal-Organic Framework

2020 ◽  
Author(s):  
Jesse Park ◽  
Brianna Collins ◽  
Lucy Darago ◽  
Tomce Runcevski ◽  
Michael Aubrey ◽  
...  
Keyword(s):  
Charge Transport ◽  
Magnetic Order ◽  
Metal Organic Framework ◽  
Metal Organic Frameworks ◽  
Magnetic Ordering ◽  
Double Exchange ◽  
Itinerant Ferromagnetism ◽  
Organic Solids ◽  
Metal Organic ◽  
Organic Framework

<b>Materials that combine magnetic order with other desirable physical attributes offer to revolutionize our energy landscape. Indeed, such materials could find transformative applications in spintronics, quantum sensing, low-density magnets, and gas separations. As a result, efforts to design multifunctional magnetic materials have recently moved beyond traditional solid-state materials to metal–organic solids. Among these, metal–organic frameworks in particular bear structures that offer intrinsic porosity, vast chemical and structural programmability, and tunability of electronic properties. Nevertheless, magnetic order within metal–organic frameworks has generally been limited to low temperatures, owing largely to challenges in creating strong magnetic exchange in extended metal–organic solids. Here, we employ the phenomenon of itinerant ferromagnetism to realize magnetic ordering at <i>T</i><sub>C</sub> = 225 K in a mixed-valence chromium(II/III) triazolate compound, representing the highest ferromagnetic ordering temperature yet observed in a metal–organic framework. The itinerant ferromagnetism is shown to proceed via a double-exchange mechanism, the first such observation in any metal–organic material. Critically, this mechanism results in variable-temperature conductivity with barrierless charge transport below <i>T</i><sub>C</sub> and a large negative magnetoresistance of 23% at 5 K. These observations suggest applications for double-exchange-based coordination solids in the emergent fields of magnetoelectrics and spintronics. Taken together, the insights gleaned from these results are expected to provide a blueprint for the design and synthesis of porous materials with synergistic high-temperature magnetic and charge transport properties. </b>

Metal-Organic Framework Transistors for Dopamine Sensing

2021 ◽  
Author(s):  
Jiajun Song ◽  
Jianzhong Zheng ◽  
Anneng Yang ◽  
Hong Liu ◽  
Zeyu Zhao ◽  
...  
Keyword(s):  
Charge Transport ◽  
Transport Properties ◽  
Metal Organic Framework ◽  
Metal Organic Frameworks ◽  
High Porosity ◽  
Two Dimensional ◽  
Metal Organic ◽  
Organic Framework

Two-dimensional (2D) conductive metal-organic frameworks (MOFs) can not only inherit the high porosity and tailorability of traditional MOFs but also exhibit unique charge transport properties, offering promising opportunities for applications...

scholarly journals Diagnosing surface versus bulk reactivity for molecular catalysis within metal–organic frameworks using a quantitative kinetic model

2020 ◽  
Vol 11 (28) ◽  
pp. 7468-7478
Author(s):  
Ben A. Johnson ◽  
Sascha Ott
Keyword(s):  
Kinetic Model ◽  
Charge Transport ◽  
Reaction Rate ◽  
Metal Organic Frameworks ◽  
Material Design ◽  
Surface Versus ◽  
Catalytic Material ◽  
Metal Organic ◽  
Intrinsic Reaction Rate ◽  
Molecular Catalysis

This report presents diagnostic criteria for determining the limiting processes of MOF-based catalysis: either mass/charge transport or the intrinsic reaction rate. This will facilitate future catalytic material design.

scholarly journals Electrical conductivity and magnetic bistability in metal–organic frameworks and coordination polymers: charge transport and spin crossover at the nanoscale

2020 ◽  
Vol 49 (15) ◽  
pp. 5601-5638 ◽  
Author(s):  
Víctor Rubio-Giménez ◽  
Sergio Tatay ◽  
Carlos Martí-Gastaldo
Keyword(s):  
Electrical Conductivity ◽  
Charge Transport ◽  
Coordination Polymers ◽  
Spin Crossover ◽  
Electronic Devices ◽  
Metal Organic Frameworks ◽  
Active Components ◽  
Metal Organic

This review aims to reassess the progress, issues and opportunities in the path towards integrating conductive and magnetically bistable coordination polymers and metal–organic frameworks as active components in electronic devices.

scholarly journals Electrical Conductivity in a Porous, Cubic Rare-Earth Catecholate

2020 ◽  
Author(s):  
Grigorii Skorupskii ◽  
Mircea Dinca
Keyword(s):  
Charge Transport ◽  
Electronic Materials ◽  
Metal Organic Frameworks ◽  
Electrical Current ◽  
Design Strategies ◽  
Electrically Conductive ◽  
Surface Areas ◽  
New Family ◽  
Structures And Properties ◽  
Metal Organic

Electrically conductive metal-organic frameworks (MOFs) provide a rare example of porous materials that can efficiently transport electrical current, a combination favorable for a variety of technological applications. The vast majority of such MOFs are highly anisotropic in both their structures and properties: only two electrically conductive MOFs reported to date exhibit cubic structures that enable isotropic charge transport. Here, we report a new family of intrinsically porous frameworks made from rare earths and hexahydroxytriphenylene that are cubic, porous, and intrinsically conductive with conductivities reaching 10−5 S/cm and surface areas of up to 780 m2/g. By expanding the list of MOFs with isotropic charge transport, these results will help improve our understanding of design strategies for porous electronic materials.<br>

scholarly journals Strategies for Controlling Through-Space Charge Transport in Metal-Organic Frameworks via Structural Modifications

Nanomaterials ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 2372
Author(s):  
Christian Winkler ◽  
Egbert Zojer
Keyword(s):  
Space Charge ◽  
Charge Transport ◽  
Density Functional ◽  
Metal Organic Frameworks ◽  
Building Blocks ◽  
Structural Defects ◽  
Transport Pathways ◽  
Metal Organic ◽  
The Individual ◽  
The Impact

In recent years, charge transport in metal-organic frameworks (MOFs) has shifted into the focus of scientific research. In this context, systems with efficient through-space charge transport pathways resulting from π-stacked conjugated linkers are of particular interest. In the current manuscript, we use density functional theory-based simulations to provide a detailed understanding of such MOFs, which, in the present case, are derived from the prototypical Zn2(TTFTB) system (with TTFTB4− corresponding to tetrathiafulvalene tetrabenzoate). In particular, we show that factors such as the relative arrangement of neighboring linkers and the details of the structural conformations of the individual building blocks have a profound impact on bandwidths and charge transfer. Considering the helical stacking of individual tetrathiafulvalene (TTF) molecules around a screw axis as the dominant symmetry element in Zn2(TTFTB)-derived materials, the focus, here, is primarily on the impact of the relative rotation of neighboring molecules. Not unexpectedly, changing the stacking distance in the helix also plays a distinct role, especially for structures which display large electronic couplings to start with. The presented results provide guidelines for achieving structures with improved electronic couplings. It is, however, also shown that structural defects (especially missing linkers) provide major obstacles to charge transport in the studied, essentially one-dimensional systems. This suggests that especially the sample quality is a decisive factor for ensuring efficient through-space charge transport in MOFs comprising stacked π-systems.

scholarly journals Is iron unique in promoting electrical conductivity in MOFs?

2017 ◽  
Vol 8 (6) ◽  
pp. 4450-4457 ◽  
Author(s):  
Lei Sun ◽  
Christopher H. Hendon ◽  
Sarah S. Park ◽  
Yuri Tulchinsky ◽  
Ruomeng Wan ◽  
...  
Keyword(s):  
Electrical Conductivity ◽  
Metal Ions ◽  
Charge Density ◽  
Charge Transport ◽  
Metal Organic Frameworks ◽  
Metal Organic

Identifying the metal ions that optimize charge transport and charge density in metal–organic frameworks is critical for systematic improvements in the electrical conductivity in these materials.

scholarly journals Isoreticular Linker Substitution in Conductive Metal–Organic Frameworks with Through-Space Transport Pathways

2020 ◽  
Author(s):  
Lilia S. Xie ◽  
Sarah S. Park ◽  
Michał J. Chmielewski ◽  
Hanyu Liu ◽  
Ruby A. Kharod ◽  
...  
Keyword(s):  
Charge Transport ◽  
Metal Organic Frameworks ◽  
Three Dimensional ◽  
Strong Interactions ◽  
Conductivity Data ◽  
Electrically Conductive ◽  
Transport Pathways ◽  
Intermolecular Contacts ◽  
Metal Organic

<p>The extension of reticular chemistry concepts to electrically conductive three-dimensional metal-organic frameworks (MOFs) has been challenging, particularly for cases in which strong interactions between electroactive linkers create the charge transport pathways. Here, we report the successful replacement of tetrathiafulvalene (TTF) with a nickel glyoximate core in a family of isostructural conductive MOFs with Mn<sup>2+</sup>, Zn<sup>2+</sup>, and Cd<sup>2+</sup>. Different coordination environments of the framework metals lead to variations in the linker stacking geometries and optical properties. Single crystal conductivity data are consistent with charge transport along the linker stacking direction, with conductivity values only slightly lower than those reported for the analogous TTF materials. These results serve as a case study demonstrating how reticular chemistry design principles can be extended to conductive frameworks with significant intermolecular contacts.</p>

scholarly journals Magnetic Ordering via Itinerant Ferromagnetism in a Metal-Organic Framework

2020 ◽  
Author(s):  
Jesse Park ◽  
Brianna Collins ◽  
Lucy Darago ◽  
Tomce Runcevski ◽  
Michael Aubrey ◽  
...  
Keyword(s):  
Charge Transport ◽  
Magnetic Order ◽  
Metal Organic Framework ◽  
Metal Organic Frameworks ◽  
Magnetic Ordering ◽  
Double Exchange ◽  
Itinerant Ferromagnetism ◽  
Organic Solids ◽  
Metal Organic ◽  
Organic Framework

<b>Materials that combine magnetic order with other desirable physical attributes offer to revolutionize our energy landscape. Indeed, such materials could find transformative applications in spintronics, quantum sensing, low-density magnets, and gas separations. As a result, efforts to design multifunctional magnetic materials have recently moved beyond traditional solid-state materials to metal–organic solids. Among these, metal–organic frameworks in particular bear structures that offer intrinsic porosity, vast chemical and structural programmability, and tunability of electronic properties. Nevertheless, magnetic order within metal–organic frameworks has generally been limited to low temperatures, owing largely to challenges in creating strong magnetic exchange in extended metal–organic solids. Here, we employ the phenomenon of itinerant ferromagnetism to realize magnetic ordering at <i>T</i><sub>C</sub> = 225 K in a mixed-valence chromium(II/III) triazolate compound, representing the highest ferromagnetic ordering temperature yet observed in a metal–organic framework. The itinerant ferromagnetism is shown to proceed via a double-exchange mechanism, the first such observation in any metal–organic material. Critically, this mechanism results in variable-temperature conductivity with barrierless charge transport below <i>T</i><sub>C</sub> and a large negative magnetoresistance of 23% at 5 K. These observations suggest applications for double-exchange-based coordination solids in the emergent fields of magnetoelectrics and spintronics. Taken together, the insights gleaned from these results are expected to provide a blueprint for the design and synthesis of porous materials with synergistic high-temperature magnetic and charge transport properties. </b>

Sign in / Sign up

Export Citation Format

Share Document