Quantum dots (QDs) with high emission efficiency have been developed by the research groups of Professor Yeon Sik Jeong and Professor Duk Young Jeon from the Department of Materials Science and Engineering, and Professor Min Seok Jang from the School of Electrical Engineering. Geon Yeong Kim, Shinho Kim, and Jinyoung Choi were listed as the joint first authors for the paper in which their discovery was published, titled “Order-of-Magnitude, Broadband-Enhanced Light Emission from Quantum Dots Assembled in Multiscale Phase-Separated Block Copolymers”.

QD-BCP composite film fabrication process

With the emergence of quantum dot OLED screens, interest in QD optoelectronics has grown. Engineering challenges existing in the application of quantum dots in optoelectronics include the low emission and excitation efficiencies, otherwise referred to as photoluminescence. Low photoluminescence is observed in pure QD materials from the interaction between adjacent dots.

KAIST research groups have taken a new approach to increase photoluminescence  by developing a composite film of QDs and block copolymer (BPC), which has a fine porous structure. This maximizes the interaction between light and quantum dots, observed in the amplification of light absorption and extraction efficiencies by four and five times, respectively. During testing of blue LEDs, the research teams noted that there was a significant increase in the composite QD-BCP film versus pure quantum dot material, which suggests the future applications of this new material in the LED display industry. This technology has already received a Korean patent.

Professor Jeong remarked that the “material has great potential for application in light emitting materials outside of quantum dots, as it increases the light emission intensity across the entire spectrum of visible light. Furthermore, due to its excellent light emission characteristics, it will play a significant role in improving the cost competitiveness of next generation displays.”

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