Sep 18: A research team led by Professor Boseok Kang of the SKKU Advanced Institute of Nanotechnology, Department of Nano Engineering, and Department of Semiconductor Convergence Engineering has raised the doping efficiency of electrically conductive plastics to a world-class level by attaching specific molecules to them, and has for the first time elucidated the underlying operating mechanism. Conducting polymers are drawing attention as a core material for wearable electronics and freely foldable displays owing to their light weight and flexibility.
To make a material such as plastic conduct electricity well, a process called “doping” is essential. Much like adding salt to water to make it conductive saltwater, doping involves introducing additives that deliver electrons within the material to enable smooth electrical flow. While tightly bonding a special molecule called an “alkylsilane” to a polymer had been known to offer excellent stability, the exact way the molecules bond and the precise reason they enhance conductivity had remained unclear—limiting broader application of this approach across various conducting plastic materials.
Using a next-generation conducting polymer material, the research team experimentally demonstrated that gas-phase alkylsilane molecules form a strong chemical bond with the polymer surface, much like magnets attracting one another. The team systematically proved a complex mechanism in which the molecule’s own intrinsic electrical property (dipole moment) is added into the mix during this process, enabling more electrons to move more freely within the polymer.
Applying this approach, the team successfully injected up to 1.79 electrons per repeating unit of the polymer’s basic structure—the highest efficiency reported to date among conducting polymer materials—while also raising the material’s electrical conductivity to over 3,000 S/cm. The team further applied this technology directly to transistor electrodes and to the transparent electrodes of light-emitting displays, confirming a dramatic improvement in the performance of actual electronic components.
Professor Boseok Kang said,
“This achievement is fundamental research that clearly elucidates the precise chemical reaction and electrical conduction mechanism between organic semiconductors and alkylsilane molecules—a process that had previously remained a mystery. As an example of how the principles of chemical bonding and electron movement taught in middle and high school science classes can be applied to cutting-edge semiconductor technology, this work is expected to significantly accelerate the development of next-generation flexible electronic devices, such as wearable healthcare devices and rollable displays.”
This research was supported by the Ministry of Science and ICT and the National Research Foundation of Korea through its International Collaborative Research Program, Mid-Career Researcher Program, and Nano and Material Technology Development Program. The findings were published as the cover paper in the July 29, 2026 issue of the Journal of the American Chemical Society, a globally renowned international academic journal.