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Updated: Sep 10, 2025
08:18
Microscopic Visualization of Porous Nanographenes Synthesized through a Combination of Solution and On-Surface Chemistry
Published on: March 4, 2021
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Lateral π-extended helical nanographenes with large spin polarization
Wenhui Niu1,2, Chi Fang1, Likun Tang3
1Max Planck Institute of Microstructure Physics Weinberg 2 06120 Halle Germany wenhui.niu@mpi-halle.mpg.de stuart.parkin@mpi-halle.mpg.de.
Chemical Science
|August 25, 2025
Summary
Researchers developed new helical nanographenes exhibiting significant chiral-induced spin selectivity (CISS). These materials show high spin polarization, paving the way for advanced organic spintronic devices.
Area of Science:
- Organic electronics
- Spintronics
- Materials science
Background:
- Chiral-induced spin selectivity (CISS) is observed in some organic molecules.
- Helicene units are known to exhibit CISS.
- Helical nanographenes (NGs) are potential candidates for CISS, but detection platforms are limited.
Purpose of the Study:
- To synthesize and characterize novel lateral extended helical nanographenes.
- To investigate the spin-selective transport properties of these NGs.
- To explore their potential for organic spintronic applications.
Main Methods:
- Developed a synthetic strategy using pre-fused oligophenylene precursors.
- Synthesized lateral extended NGs with undecabenzo[7]helicene units.
- Utilized magneto-conductive atomic force microscopy (mc-AFM) and magnetoresistance (MR) measurements.
Main Results:
- Achieved high yields in synthesizing novel helical NGs.
- Demonstrated excellent chiroptical properties (strong circular dichroism, large dissymmetry factors).
- Observed significant spin polarization (up to 80%) and robust MR (1.5%) at room temperature.
Conclusions:
- Lateral extended helical NGs are successfully synthesized and exhibit strong CISS effect.
- These NGs show promising spin-polarized transport properties.
- Identified as potential quantum materials for organic spintronic devices.
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