A research team has developed a revolutionary two-dimensional polyaniline (2DPANI) crystal that overcomes major conductivity limitations in polymers. Its unique multilayered structure allows metallic charge transport, setting the stage for new applications in electronics and materials science.
An international team of researchers has successfully created a multilayered two-dimensional polyaniline (2DPANI) crystal, demonstrating exceptional conductivity and a unique ability to transport charge in a metallic-like manner. Their findings were published on February 5 in Nature.
Conducting polymers — such as polyaniline, polythiophene, and polypyrrole — are valued for their electrical conductivity and offer a promising alternative to traditional semiconductors and metals. They are lightweight, flexible, and cost-effective, making them attractive for various technological applications.
Despite their potential, one major challenge has been achieving efficient charge transport, especially between polymer chains. This limitation has restricted their overall performance and slowed their adoption in practical applications.
A Novel Approach to 2DPANI Synthesis
In response to this challenge, researchers from the Ningbo Institute of Materials Technology and Engineering (NIMTE) of the Chinese Academy of Sciences (CAS), TU Dresden, the Max Planck Institute of Microstructure Physics, and CIC nanoGUNE BRTA have developed a novel 2DPANI crystal by virtue of a topology-directed 2D polymerization of aniline using an anionic surfactant monolayer on the water surface.
The 2DPANI crystal has a domain size of 130–160 square micrometers (μm²) and a thickness ranging from tens to hundreds of nanometers. It features columnar π arrays with an interlayer spacing of 3.59 angstroms (Å) and rhombohedral lattices, a specific type of crystal structure formed by interwoven polyaniline chains. This structure facilitates strong in-plane conjugation and interlayer electronic coupling, as confirmed by electron spin resonance spectroscopy and first-principles calculations.
Impressive Conductivity and Charge Transport
The synthesized conducting polymer exhibited a Drude-type conductivity, with an extrapolated direct current conductivity of approximately 200 S/cm. An anisotropic charge transport was also observed, with out-of-plane and in-plane conductivities measuring about 7 S/cm and 16 S/cm, respectively.
Notably, vertical devices demonstrated increasing conductivity at lower temperatures, which is characteristic of metallic out-of-plane transport.
This advancement in conducting polymer research addresses the limited charge transport issue caused by the insufficient structural ordering and electronic coupling. The study also offers insights into three-dimensional metallic conductivity, opening new avenues for the development of electrodes, electromagnetic shielding, and sensors.
Reference: “Two-dimensional polyaniline crystal with metallic out-of-plane conductivity” by Tao Zhang, Shu Chen, Petko St. Petkov, Peng Zhang, Haoyuan Qi, Nguyen Ngan Nguyen, Wenjie Zhang, Jiho Yoon, Peining Li, Thomas Brumme, Alexey Alfonsov, Zhongquan Liao, Mike Hambsch, Shunqi Xu, Lars Mester, Vladislav Kataev, Bernd Büchner, Stefan C. B. Mannsfeld, Ehrenfried Zschech, Stuart S. P. Parkin, Ute Kaiser, Thomas Heine, Renhao Dong, Rainer Hillenbrand and Xinliang Feng, 5 February 2025, Nature.
DOI: 10.1038/s41586-024-08387-9
The study was supported by the National Natural Science Foundation of China and the Excellent Youth Foundation of Zhejiang Province, among other organizations.
Never miss a breakthrough: Join the SciTechDaily newsletter.
1 Comment
A way might be found to make these into circuitboards.
The conducting sheet would have nonconducting areas burned into it via laser printing, which could change the crystalline structure to a nonconducting glassy structure.