- Developing transistors that light up through electrochemical doping techniques

- Cover article selected by the international journal Advanced Materials Technologies 

A research team led by Professor Jung Hwa Seo of the University of Seoul’s Department of Physics and Department of Intelligent Semiconductor Engineering has developed an innovative light-emitting device technology that will accelerate the commercialization of wearable and transparent displays. Prof. Seo’s team has realized a light-emitting transistor device with electrochemical doping technology, which is expected to dramatically simplify the complex multilayer structure process in next-generation displays and enable high-efficiency and low-cost production.

the lightemitting mechanism of an electrochemical lightemitting transistor and its electric field and photoluminescence spectra

Cover image from the 2024 volume 9 issue 20 of the journal Advanced Materials Technologies

▶ (a–d) the light-emitting mechanism of an electrochemical light-emitting transistor and (e) its electric field and photoluminescence spectra.

Cover image from the 2024 volume 9, issue 20, of the journal Advanced Materials Technologies

Jung Hwa Seo’s team has developed a technology to electrochemically dope new polyelectrolyte materials with metal ions (Li＋, Cu2＋) bonded to poly(9-vinylcarbazole) polymers into luminescent materials. The team successfully realized a light-emitting transistor device with excellent light-emitting efficiency and elucidated the electron-hole migration and coupling mechanisms due to the migration of metal ions.

Electrochemical doping technology is expected to be widely used in next-generation displays, such as wearable and transparent displays, as it dramatically simplifies the complex multilayer structure process of existing light-emitting electronic devices and lowers production costs, which is advantageous for achieving high integration and for large areas.

The study was led by first author, Yu Jung Park, and a postdoctoral researcher, Jin Hee Lee, from the Department of Physics at the University of Seoul, in collaboration with Bright Walker from the Department of Chemistry at Kyung Hee University and Han-Ki Kim from the Department of New Materials at Sungkyunkwan University.

The findings were published online on May 16 in Wiley’s top-ranked international journal in the field of materials (Q1), Advanced Materials Technologies, with the title “Photoelectron Spectroscopic Study of the Interfacial Electronic Structures of Metal-Ion Containing Polyelectrolytes on ITO Substrates: Ambipolar Charge Injection and Bright Light Emission in Hybrid Oxide/Polymer Transistors Doped with Poly(9-Vinylcarbazole) Based Polyelectrolytes,” and the article was selected as the cover paper in the October 21 issue.

This research was supported by the Basic Research Laboratory Support Program of the National Research Foundation of Korea, the Mid-career Researchers Support Program, and the Creative and Challenging Research Foundation Support Program.