Halide perovskite, which is attracting attention as a fabric applicable to numerous next-generation photovoltaic devices comparable to solar cells, photodetectors, and LEDs, is the one material that may 100% satisfy the colour coordinate standard of the display called ‘Rec. 2020’. Nonetheless, despite this excellent performance, within the case of deep blue perovskite LEDs, significantly low efficiency and low brightness were reported. The KAIST research team is a hot topic for presenting a technology that solves the colour instability problem seen in deep blue perovskite LEDs while achieving high brightness.
The Korea Advanced Institute of Science and Technology (KAIST, President Kwang-Hyung Lee) announced on the tenth that a research team led by Professor Jeong-Yong Lee of the Department of Electrical and Electronic Engineering has made a groundbreaking solution to the issue of color change and low brightness depending on the driving voltage of deep blue perovskite LEDs, that are attracting attention as next-generation displays as a result of their high color purity.
Professor Lee Jeong-yong’s research team developed a technology to effectively solve the chronic problems of deep blue LEDs, that are known to have high color purity, amongst perovskite LEDs, in response to the demands of the display industry, which is increasingly demanding high color purity.
First, within the case of the deep blue LED made by mixing several types of ions, the issue of color changing depending on the dimensions of the driving voltage and the issue of low brightness, which is a very powerful indicator for commercialization, needed to be solved before commercialization could come slightly closer. Professor Lee Jeong-yong’s research team was in a position to solve these problems in a groundbreaking way by utilizing the chloride ion emptiness targeting ligand strategy. Based on this, it is predicted that it would give you the chance to come back one step closer to commercialization by presenting insights that may solve the chronic problems of the deep blue perovskite LED.
The research team targeted and blocked halide ion channels that cause phase separation as a result of ion movement, which is the explanation for color instability, and effectively suppressed ion movement by strategically blocking the channels. As well as, they chose candidate groups of materials that might apply the strategy and showed performance changes and color stability trends in line with changes within the length of the carbon chain, suggesting a brand new perspective to unravel the issues of deep blue perovskite LEDs.
Through this study, the very best brightness (2700 nit) among the many performances of deep blue perovskite LEDs reported up to now was reported. Through this, it is predicted that the commercialization of next-generation perovskite displays could be further accelerated by producing a deep blue perovskite LED with a level of brightness that may solve the outdoor visibility problem by which the display is just not visible in an out of doors lighting environment with strong sunlight.
“This study effectively solved the chronic color instability problem of deep blue perovskite LEDs made by mixing different halide ions,” said first writer Seungjae Lee, a doctoral student. “At the identical time, we created a wonderful deep blue perovskite LED with high brightness of over 2000 nits, which is the utmost brightness required for recent smartphones, further reducing the gap with the already high-level green and red LEDs, thereby opening up the potential for applying it to RGB displays.”
This study, by which KAIST Department of Electrical and Electronic Engineering doctoral candidate Seungjae Lee and Dr. Junho Kim participated as first authors, was officially published within the May 2024 online edition of ‘Science Advances,’ a sister journal of the international academic journal ‘Science.’
Meanwhile, this study was conducted with the support of the National Research Foundation of Korea (NRF).
Reporter Kim Tae-yong future@aitimes.com
