Tunable Charge Transport and Spin Dynamics in Two-Dimensional Conjugated Metal-Organic Frameworks
Yang Lu1,2,3, Ziqi Hu4,5, Petko Petkov6
1Max Planck Institute of Microstructure Physics, 06120 Halle (Saale), Germany.
Journal of the American Chemical Society
|January 17, 2024
Summary
Controlling interlayer stacking in two-dimensional conjugated metal-organic frameworks (2D c-MOFs) enhances spin properties. This strategy boosts spin density and relaxation time, crucial for developing advanced spintronics devices.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Chemistry
Background:
- Two-dimensional conjugated metal-organic frameworks (2D c-MOFs) show promise for electronics and spintronics due to their conductivity and persistent organic radicals.
- Strong interlayer π-interactions in stacked 2D c-MOFs hinder spin qubit potential by annihilating spin centers and accelerating spin relaxation.
Purpose of the Study:
- To precisely tune charge transport and spin dynamics in 2D c-MOFs.
- To investigate the effect of controlled interlayer stacking on spin properties and electrical conductivity.
Main Methods:
- Introduction of bulky side groups on conjugated ligands to modify interlayer stacking from serrated to staggered.
- Characterization of electrical conductivity and spin dynamics, including spin density and spin-lattice relaxation time (T1).
Main Results:
- Dislocation of 2D c-MOF layers to staggered stacking significantly weakened interlayer interactions.
- Electrical conductivity decreased by 6 orders of magnitude; spin density increased over 30-fold.
- Spin-lattice relaxation time (T1) extended up to ~60 μs, surpassing reference materials with fast spin relaxation.
Conclusions:
- Controlled interlayer stacking is a viable strategy to enhance spin dynamics in 2D c-MOFs.
- The findings provide a bottom-up approach for developing MOF-based spintronics and spin qubits.
- Spinless polaron or bipolaron pairs are identified as critical in charge transport within these 2D c-MOFs.
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