Dankook University Professor Kang Sunwoo Develops Brighter and Longer-Lasting Blue OLED Device

Professor Sunwoo Kang's research team in the Department of Chemistry at Dankook University has succeeded in developing a blue phosphorescent OLED (organic light-emitting diode) device that is brighter and lasts longer. Professor Sunwoo Kang, Dankook University.

Dankook University announced on the 7th that a research team led by Professor Kang Sunwoo from the Department of Chemistry has succeeded in developing a brighter and longer-lasting blue phosphorescent OLED (organic light-emitting diode) device.

Currently, OLEDs (organic light-emitting diodes) are the most widely used displays in mobile devices such as smartphones and tablets, and are classified as either 'phosphorescent' or 'fluorescent' depending on their light emission mechanism. Phosphorescent OLEDs convert electrical energy to light with nearly 100% efficiency, while fluorescent OLEDs achieve only about 25% efficiency.

As a result, red and green devices have commercialized phosphorescent OLEDs, but blue phosphorescent OLEDs still rely on fluorescent OLEDs due to their short lifespan and low stability. In particular, blue phosphorescent OLEDs are difficult to commercialize because their short lifespan leads to display burn-in (degradation) during prolonged use.

Professor Kang's research team, in collaboration with Professor Kim Taekyung of Hongik University, Professor Hong Wanpyo of Gachon University, and Rodin Co., Ltd., embarked on the development of blue phosphorescent OLED devices. They devised a design method that effectively suppresses molecular vibrations, which hinder the efficiency, lifespan, and color purity of existing devices (BD-02).

By applying a molecular group called spirofluorene to the carbazole group, which constitutes the blue phosphorescent emitter, the team reduced molecular vibrations. The device developed by the research team demonstrated 113% higher luminous efficiency and a 138% longer lifespan compared to the existing device (BD-02).

Professor Kang Sunwoo stated, "The newly developed platinum-based Pt(II) complex suppresses molecular vibrations and presents a basic design method for molecular structures that achieve high efficiency and long lifespan, which will further accelerate the commercialization of blue phosphorescent OLED devices."

Meanwhile, this research, in which Professor Kang participated as a co-corresponding author, was recently published in the materials engineering journal ‘Advanced Materials (IF = 27.4)’.