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Backbone Engineering of Carbon-Centered NHC-Derived Diradicals: From Electronic State Tuning to High-Performance
Xiao-Xu Liu1, Lianghui Li2, Xin Li1,3
1College of Chemistry and Materials Science, Northwest University, Xi'an, P. R. China.
Advanced Materials (Deerfield Beach, Fla.)
|May 5, 2026
Summary
Researchers developed new carbon-centered neutral diradicals using N-heterocyclic carbene backbones. These diradicals enable precise control over spin states and exhibit high performance in organic field-effect transistors (OFETs).
Area of Science:
- Organic Chemistry
- Materials Science
- Organic Electronics
Background:
- Diradicals possess unique electronic properties valuable for organic electronics.
- Challenges exist in controlling their electronic states and device performance.
Purpose of the Study:
- To synthesize and characterize tetraphenylethylene-bridged salts and their neutral diradical counterparts.
- To establish a backbone engineering strategy for controlling spin states in N-heterocyclic carbene (NHC) diradicals.
Main Methods:
- Synthesis of tetraphenylethylene-bridged salts and their reduction to diradicals.
- Characterization of electronic properties and open-shell character.
- Fabrication and testing of an organic field-effect transistor (OFET) device using a synthesized diradical.
Main Results:
- Extended conjugation and electron-withdrawing NHC backbones enhanced open-shell character.
- A backbone engineering strategy provided precise control over spin states and diradical character.
- Compound 2d achieved a record-high hole mobility of 4.53 cm2·V-1·s-1 in an OFET device.
Conclusions:
- The developed backbone engineering strategy enables precise control over carbon-centered NHC diradicals.
- The high-performance OFET device demonstrates the potential of these diradicals for advanced organic electronics.
- This approach facilitates the development of functional open-shell organic semiconductors.
Keywords:
N‐heterocyclic carbenecarbon‐centered diradicaldiradical characteropen‐shell organic semiconductororganic field‐effect transistorMore Related Videos
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