Chiral two-dimensional conjugated metal-organic frameworks with high spin polarization

Area of Science:

• Materials Science
• Organic Chemistry
• Solid-State Physics

Background:

• Two-dimensional conjugated metal-organic frameworks (c-MOFs) are promising organic 2D crystal materials.
• Chirality in 2D crystals can lead to unique physical phenomena, but its precise implementation in 2D c-MOFs remains a challenge.

Purpose of the Study:

• To demonstrate the synthesis of chiral 2D c-MOFs.
• To achieve tunable chiral expression and chirality amplification.
• To explore potential applications in chiral spintronics.

Main Methods:

• Utilized a side chain-induced chirality amplification strategy.
• Introduced chiral substitutions into the 2,3,7,8,12,13-hexaiminotriindole ligand.
• Employed steric control with chiral naphthylethyl substitution to tune distortion angles.
• Measured spin polarization using magnetic-conductive atomic force microscopy (mc-AFM).

Main Results:

• Successfully synthesized chiral 2D c-MOFs with tunable chirality.
• Observed significant chirality amplification, with distortion angles increasing from 2.3° to 7.0°.
• Achieved exceptional spin polarization of up to 96.9%, among the highest reported.
• Demonstrated the correlation between steric control and chirality amplification.

Conclusions:

• The side chain-induced chirality amplification strategy is effective for creating chiral 2D c-MOFs.
• Tunable chirality and high spin polarization make these materials suitable for spintronics.
• This research opens new avenues for designing advanced chiral 2D materials.