|author||S. H. Park, A. Hong, J.-H. Kim, H. Yang, K. Lee, H. S. Jang|
|journal||ACS Appl. Mater. Interfaces, 2015, 7, 6764.|
In this study, we report bright yellow-green-emitting CuInS2 (CIS)-based quantum dots (QDs) and two-band white light-emitting diodes (LEDs) using them. To achieve high quantum efficiency (QE) of yellow-green-emitting CIS QDs, core/shell/shell strategy was introduced to high quality CIS cores (QE = 31.7%) synthesized by using metal-oleate precursors and 1-dodecanethiol. The CIS/ZnS/ZnS QDs showed a high QE of 80.0% and a peak wavelength of 559 nm under the excitation of 450 nm, which is well matched with dominant wavelength of blue LEDs. The formation of core/shell/shell structure was confirmed by X-ray diffraction, transmission electron microscopy, and inductively coupled plasma-optical emission spectroscopy analyses. Intense and broad yellow-green emission band of the CIS/ZnS/ZnS is beneficial for bright two-band white light. When the CIS/ZnS/ZnS was coated on the blue LEDs, the fabricated white LED showed bright natural white light (luminous efficacy (η(L)) = 80.3 lm·W(-1), color rendering index (R(a)) = 73, correlated color temperature (T(c)) = 6140 K). The QD-white LED package showed a high light conversion efficiency of 72.6%. In addition, the CIS/ZnS/ZnS-converted white LED showed relatively stable white light against the variation of forward bias currents of 20-150 mA [color coordinates (x, y) = (0.3320-0.3207, 0.2997-0.2867), R(a) = 70-72, T(c) = 5497-6375 K].
« Prev 109. Colourimetric redox-polyaniline nanoindicator for in sit...109. Colourimetric redox-polyaniline nanoindicator for in sit... 2016.05.18by 〈
107. Skeletal platinum-based octahedral nanoframe with Cartes... Next »107. Skeletal platinum-based octahedral nanoframe with Cartes... 2016.05.18by 〉
Designed by sketchbooks.co.kr / sketchbook5 board skin