Professor Kim Taekyung and his team from Hongik University's Department of Nanomaterials Engineering publish research in Materials Horizons

The Cooperative Program in Information Display Engineering and the Department of of Nanomaterials Engineering at Hongik University, led by Professor Kim Taekyung, has achieved a global breakthrough.  On the 8th of this month, Professor Kim's research team announced that through joint research, they have discovered the photonic mechanism behind the high quantum utilisation efficiency of blue fluorescent organic light emitting diodes.

In OLED (Organic Light-Emitting Diode) research, the most persistent challenge has been improving the efficiency and lifespan of the blue emitters traditionally used. Professor Kim Taekyung, who has been researching blue OLED exclusively from 2010 to 2019 during his tenure at Samsung Display, has a particular interest in this research.

This study was conducted in collaboration with Dr. Kang Sunwoo from Samsung Display, Professor Kim Woojae from the Department of Chemistry at Yonsei University, and Professor Yoon Seungsoo from the Department of Chemistry at Sungkyunkwan University. The team developed a new material with a high-level reverse interphase switching (hRISC) phenomena for blue fluorescent organic light-emitting diodes, achieving superior quantum utilisation efficiency compared to conventional materials.

The findings were recently published in Materials Horizons, a world-leading journal in the field of chemistry and materials, and have garnered significant attention in the international academic community. Materials Horizons is a journal published by The Royal Society of Chemistry (RSC) and has grown strongly since its launch in 2014 to become a leading journal in the field of chemistry and materials.

The research included doctoral candidate Kim Kiju and master's student Kim Jaesung from the Cooperative Program in Information Display Engineering, who participated as Co-first authors. This study, supported by the Electronics Component Industry Technology Development and Display Innovation Process Platform Establishment projects, under the Basic Research Program for Engineering and Science Fields by the Korea Foundation for the Advancement of Science & Creativity, has reaffirmed Hongik University's high-level research capabilities. In particular, students were able to critically analyze the data obtained from experiments during the research, derive meaningful conclusions, and learn logical frameworks to validate these conclusions experimentally and theoretically.

"I have been continuously working on blue OLEDs only.  It was challenging to theoretically demonstrate through experimental research that blue OLEDs can emit light without following specific principles.  I believe that our team succeeded in addressing this issue, leading to the publication of our paper in a prestigious journal. Of course, the results of this research cannot improve the efficiency and lifetime of all blue OLEDs, but I think it can lay a small foundation for suggesting new development directions. We will continue to conduct various research to improve the efficiency and lifetime of blue OLEDs, and we will continue to collaborate with both industry and academia."

- Professor Kim Taekyung, Department of of Nanomaterials Engineering, Hongik University

The researchers introduced a new material that uses the phenomenon of high-level reverse interstitial transition (hRISC) in combination with triplet-triplet decay (TTF), to increase the quantum utilisation efficiency of blue fluorescent organic light-emitting diodes.  As a result, they improved the quantum efficiency to 64.3%, compared to the existing 40%.

Through these achievements, Hongik University has demonstrated internationally leading technological and research capabilities. Moving forward, Hongik University strives to continue to strengthen its position as a global technology leader through continuous research and innovation.

Online Communications Reporter, Kim Minju