Wavelength dependent color conversion of CdSe/ZnS core/shell nanocrystals for white LEDs
Demir, H. V.
Conference Proceedings - Lasers and Electro-Optics Society Annual Meeting-LEOS
280 - 281
MetadataShow full item record
Please cite this item using this persistent URLhttp://hdl.handle.net/11693/28600
Nanocrystals (NCs) provide narrow emission spectrum that can be conveniently tuned using quantum size effect. This ability to adjust and control emission spectrum of NCs makes them strong candidates for use in white color conversion light emitting diodes. For example, they are possibly be used for solid state lighting applications including indoor lighting, architectural lighting and scotopic street lighting, where spectrally tuned color conversion is necessary. In device research CdSe/ZnS core/shell nanocrystals are the most commonly used ones because of their good electronic isolation coming from ZnS shells and the resulting high quantum efficiency (QE) (i.e., >50% in solution) . However, when these nanocrystals are integrated into the solid film, e.g., for white light generation, their in-film QE undesirably drops (despite their high QE in solution). Hence, this adversely affects the overall efficiency of the integrating devices that incorporate these NCs . There have been various studies to understand the in-film optical properties of CdSe/ZnS core/shell NCs [3-5]. However, their spectrally resolved in-film quantum efficiency (i.e., the ratio of the number of photons emitted by the nanocrystal film to the number of photons absorbed in the nanocrystal film) and their photon conversion efficiency (i.e., the ratio of the number of photons emitted by the nanocrystal film to the number of photons incident to the nanocrystal film) have not been investigated in these previous studies. © 2009 IEEE.
- Conference Paper 2294
Showing items related by title, author, creator and subject.
Power conversion and luminous efficiency performance of nanophosphor quantum dots on color-conversion LEDs for high-quality general lighting Erdem, T.; Nizamoglu, S.; Demir, H. V. (2012)For high-quality general lighting, a white light source is required to exhibit good photometric and colorimetric performance along with a high level of electrical efficiency. For example, a warm white shade is desirable ...
Computational study of power conversion and luminous efficiency performance for semiconductor quantum dot nanophosphors on light-emitting diodes Erdem, T.; Nizamoglu, S.; Demir, H. V. (Optical Society of American (OSA), 2012)We present power conversion efficiency (PCE) and luminous efficiency (LE) performance levels of high photometric quality white LEDs integrated with quantum dots (QDs) achieving an averaged color rendering index of ≥90 (with ...
Mutlugun, E.; Hernandez-Martinez P.L.; Eroglu, C.; Coskun, Y.; Erdem, T.; Sharma V.K.; Unal, E.; Panda, S.K.; Hickey, S.G.; Gaponik, N.; Eychmüller, A.; Demir, H. V. (2012)We propose and demonstrate the fabrication of flexible, freestanding films of InP/ZnS quantum dots (QDs) using fatty acid ligands across very large areas (greater than 50 cm × 50 cm), which have been developed for remote ...