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Development of Heterogeneous Enantioselective Catalysts using Chiral Metal-Organic Frameworks MOFs
Published on: January 17, 2020
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Covalent Organic Frameworks with Tunable Chirality for Chiral-Induced Spin Selectivity.
Xing Han1, Chao Jiang1, Bang Hou1
1School of Chemistry and Chemical Engineering, Frontiers Science Center for Transformative Molecules and State Key Laboratory of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240, China.
Journal of the American Chemical Society
|February 28, 2024
Summary
Chiral covalent organic frameworks (CCOFs) demonstrate efficient chirality-induced spin selectivity (CISS) for spin filter applications. This research introduces CCOF-9-Co, a novel material exhibiting significant spin polarization for advanced spintronic devices.
Area of Science:
- Materials Science
- Organic Chemistry
- Spintronics
Background:
- Chiral covalent organic frameworks (CCOFs) show promise for enantioselective applications.
- Chirality-induced spin selectivity (CISS) offers a novel route for spin-polarized current injection without magnetic layers.
- Exploiting CISS within CCOFs remains an underexplored research area.
Purpose of the Study:
- To investigate CCOFs as a platform for developing spin filter materials with efficient CISS.
- To design and synthesize a new family of Zn(salen)-based 2D CCOFs.
- To explore the CISS effect in a cobalt-substituted CCOF.
Main Methods:
- Synthesis of CCOFs-9-12 via imine condensation.
- Enantioselective adsorption studies using racemic drugs.
- Fabrication and characterization of CCOF-9-Co.
- Magnetic conductive atomic force microscopy (MC-AFM) to measure CISS.
- Magnetic circular dichroism (MCD) spectroscopy.
Main Results:
- CCOF-9 demonstrated high enantioselectivity (up to 97% ee) for racemic drug adsorption.
- CCOF-9-Co exhibited enhanced conductivity and retained crystallinity and porosity.
- MC-AFM revealed a significant CISS effect in CCOF-9-Co (88-94% spin polarization ratio).
- MCD confirmed the CISS phenomenon under an external magnetic field.
Conclusions:
- CCOFs are a viable platform for creating spin filter materials with efficient CISS.
- CCOF-9-Co represents a novel material with substantial potential for spintronic applications.
- This study opens avenues for designing new crystalline polymers with strong CISS effects.
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