π-conjugated polymers are a class of molecules featuring an alternation of single and double bonds along their backbone, which enables delocalized π-electrons. Their unique electronic structure makes them highly conductive and very attractive to design applications such as solar cells or light-emitting diodes. To enhance their electronic properties, π-conjugated polymers are often doped. However, the structure and stability of the polymer suffers.
In a new study, researchers introduce an unprecedented reaction, coined indenyl coupling, to design highly conducting carbon-based polymers. They demonstrated the possibility to bond indane-based monomers in an extremely selective and efficient way, for fabricating π-conjugated polymers on a surface that host intrinsic solitons. The researchers exploit the structural parity of the polymers to design in-gap soliton states which spatially extends several nanometers along the longitudinal backbone.
The results, recently published in Nature Synthesis, answer a fundamental question in materials science: it is possible to experimentally synthetize highly conducting polymers without the need of external doping. The authors demonstrate that theoretical predicted concepts of structural parity can be an essential factor to consider when designing tailored nanomaterials hosting topological quasiparticles. This approach could lead to more efficient, cost-effective, and sustainable electronic devices featuring 1D wires.
This work is the result of a collaboration between physicists and chemists at the Madrid Institute for Advanced Studies in Nanoscience (IMDEA Nanociencia), Centro Singular de Investigación en Química Biolóxica e Materiais Moleculares (CiQUS), Universidade de Santiago de Compostela, the Institute of Physics of the Czech Academy of Science and Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC) and is partially funded by the accreditation Excellence Severo Ochoa awarded to IMDEA Nanociencia (CEX2020-001039-S) and by the accreditation Centro de Investigación de Galicia awarded to CiQUS (ED431G 2019/03).
Reference
Kalyan Biswas, Jesús Janeiro, Aurelio Gallardo, Marco Lozano, Ana Barragán, Berta Álvarez, Diego Soler-Polo, Oleksandr Stetsovych, Andrés Pinar Solé, Koen Lauwaet, José M. Gallego, Dolores Pérez, Rodolfo Miranda, José I. Urgel*, Pavel Jelínek*, Diego Peña* and David Écija*. Designing highly delocalized solitons by harnessing the structural parity of π-conjugated polymers. Nat. Synth (2024)
https://doi.org/10.1038/s44160-024-00665-8