On June 4th, Prof. Luo Xiaobing and his team's paper entitled as Targeting cooling for quantum dots in white QDs-LEDs by hexagonal boron nitride platelets with electrostatic bonding was published online on Advanced Functional Materials. This is the latest research result of heat dissipation for quantum dots in white QDs-LEDs.
The paper was selected as the Back Cover, with HUST as the first unit and Ph. D Xie Bin of School of Energy as the first author. Prof. Luo Xiaobing and Associate Professor Wang Kai are the corresponding authors.
Resent years, white light-emitting diodes (WLEDs) based on semiconductor nanocrystals-quantum dots (QDs) have attracted widespread attetion from researchers and industry due to their high luminous efficiency, excellent color rendering capability and flexible wavelength-tuning. However, QDs give rise to heat generation problem while giving out light. For lack of effective cooling measures, traditional WLEDs are hard to conduct heat through silicone, a low-thermal conductivity, which induces high-temperature quenching issues of QDs and severely hinders their potential applications. The current heat-conducting enhancer like grphene, carbon nanotubes cannot solve the heat generation problem because of their severe light-absorbing properties.
In Prof. Luo Xiaobing and his team's work, this problem is attempted by targeting cooling of the QDs by electrostatically bonding QDs onto the hexagonal boron nitride (hBN) platelets without sacrificing the optical performance of WLEDs. The red-emissive QDs/hBN composites are mixed with yellow-emissive phosphor to fabricate QDs/hBN-WLEDs. Due to the effective heat transfer channels established by the QDs/hBN, the heat could be dissipated efficiently to ambient air. And experiments show that the working temperature of WLEDs is reduced by 22.7 ℃ at 300 mA when the additive volume of QDs/hBN is 2.2%. The present strategy can improve heat dissipation for high power and high stability WLEDs lighting and display products without sacrificing the optical performance.