- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Effects of Hexagonal Boron Nitride Sheets on the Optothermal Performances of Quantum Dots-Converted White LEDs
摘要: Recently, quantum dots-converted white light-emitting diodes (QDs-WLEDs) are attracting numerous attention due to their high luminous efficiency and excellent color quality. As for color conversion material, the quantum dots (QDs) are commonly embedded into a low-thermal-conductivity polymer matrix. In this case, their generated heat during the photoluminescence process can hardly be dissipated into the heat sink, leading to a high working temperature and reduced lifetime. Adding particles with high thermal conductivity to the QDs layer can enhance its thermal conductivity, and thus reduce QDs’ working temperature. At the same time, these particles may affect the optical properties of QDs. However, this problem has still not been deeply studied. In this article, we systematically investigated the effects of the highly thermal-conductive hexagonal boron nitride sheets (hBNSs) on the optothermal performances of QDs/phosphor film in white light-emitting diodes (WLEDs). The thermal conductivity of QDs/phosphor film was significantly increased by 24% after adding 5wt% of 45-μm-diameter hBNS. As for the optical performance, the transparency of the silicone gel film with 45-μm-diameter hBNS was much better than that with 6–9-μm-diameter hBNS under the same weight fraction. Furthermore, the scattering effect of hBNS plays a more important role in enhancing the light conversion performance of QDs than that of phosphor. At last, a color stability test showed the increasing rate of correlated color temperature (IRCCT) of hBNS-added WLEDs are 21% smaller than that of common WLEDs after working 153 h, meaning a better QDs stability in hBNS-added WLEDs.
关键词: light conversion,quantum dots (QDs),Hexagonal boron nitride sheets (hBNSs),thermal conductivity
更新于2025-09-11 14:15:04
-
14.2: <i>Invited Paper:</i> Quantum Yield Measurement Using Organic Dyes as References for Semiconductor Nanocrystals
摘要: A method of using series of organic dyes as reference to measure the quantum yield efficiency (QY) for semiconductor nanocrystals (Quantum Dots, QDs) in solution state is reported. In the proposed method, the sensitivity of the fluorescence spectrophotometer on wavelength as well as the excitation power intensity is considered to improve the accuracy.
关键词: Semiconductor Nanocrystals,Quantum Dots,QDs,Quantum Yield Efficiency Measurment
更新于2025-09-09 09:28:46