Abstract
Colloidal quantum-dot light-emitting diodes have recently received considerable attention due to their ease of colour tunability, high brightness and narrow emission bandwidth. Although there have been rapid advances in luminance, efficiency and lifetime, device performance is still limited by the large energy barriers for hole and electron injection into the quantum-dot layer. Here, we show that by crosslinking the colloidal quantum-dot layer, the charge injection barrier in a red-light-emitting quantum-dot light-emitting diode may be considerably reduced by using a sol–gel TiO2 layer for electron transport. The device architecture is compatible with all-solution device fabrication and the resulting device shows a high luminance (12,380 cd m−2), low turn-on voltage (1.9 V) and high power efficiency (2.41 lm W−1). Incorporation of the technology into a display device with an active matrix drive backplane suggests that the approach has promise for use in high-performance, easy-to-fabricate, large-area displays and illumination sources.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 12 print issues and online access
$209.00 per year
only $17.42 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Colvin, V. L., Schlamp, M. C. & Alivisatos, A. P. Light-emitting diodes made from cadmium selenide nanocrystals and a semiconducting polymer. Nature 370, 354–357 (1994).
Dabbousi, B. O., Bawendi, M. G., Onitsuka, O. & Rubner, M. F. Electroluminescence from CdSe quantum-dot/polymer composites. Appl. Phys. Lett. 66, 1316–1318 (1995).
Schlamp, M. C., Peng, X. & Alivisatos, A. P. Improved efficiencies in light emitting diodes made with CdSe(CdS) core/shell type nanocrystals and a semiconducting polymer. J. Appl. Phys. 82, 5837–5842 (1997).
Mattoussi, H. et al. Electroluminescence from heterostructures of poly(phenylene vinylene) and inorganic CdSe nanocrystals. J. Appl. Phys. 83, 7965–7974 (1998).
Coe, S., Woo, W.-K., Bawendi, M. & Bulović, V. Electroluminescence from single monolayers of nanocrystals in molecular organic devices. Nature 420, 800–803 (2002).
Tessler, N., Medvedev, V., Kazes, M., Kan, S. & Banin, U. Efficient near-infrared polymer nanocrystal light-emitting diodes. Science 295, 1506–1508 (2002).
Chaudhary, S., Ozkan, M. & Chan, W. C. W. Trilayer hybrid polymer–quantum dot light-emitting diodes. Appl. Phys. Lett. 84, 2925–2927 (2004).
Coe-Sullivan, S., Steckel, J. S., Woo, W.-K., Bawendi, M. G. & Bulović, V. Large-area ordered quantum-dot monolayers via phase separation during spin-casting. Adv. Funct. Mater. 15, 1117–1124 (2005).
Caruge, J.-M., Halpert, J. E., Bulović, V. & Bawendi, M. G. NiO as an inorganic hole-transporting layer in quantum dot light-emitting devices. Nano Lett. 6, 2991–2994 (2003).
Mueller, A. H. et al. Multicolor light-emitting diodes based on semiconductor nanocrystals encapsulated in GaN charge injection layers. Nano Lett. 5, 1039–1044 (2005).
Sun, Q. et al. Bright, multicolored light-emitting diodes based on quantum dots. Nature Photon. 1, 717–722 (2007).
Caruge, J. M., Halpert, J. E., Wood, V., Bulović, V. & Bawendi, M. G. Colloidal quantum-dot light-emitting diodes with metal-oxide charge transport layers. Nature Photon. 2, 247–250 (2008).
Redecker, M., Bradley, D. D. C., Inbasekaran, M., Wu, W. W. & Woo, E. P. High mobility hole transport fluorene-triarylamine copolymers. Adv. Mater. 11, 241–246 (1999).
Lim, J. et al. Preparation of highly luminescent nanocrystals and their application to light-emitting diodes. Adv. Mater. 19, 1927–1932 (2007).
Kim, J. Y. et al. New architecture for high efficiency polymer photovoltaic cells using solution-based titanium oxide as an optical spacer. Adv. Mater. 18, 572–576 (2006).
Hikmet, R. A. M., Talapin, D. V. & Weller, H. Study of conduction mechanism and electroluminescence in CdSe/ZnS quantum dot composites. J. Appl. Phys. 93, 3509–3514 (2003).
Kepler, R. G. et al. Electron and hole mobility in tris(8-hydroxyquinolinolato-N1,O8) aluminum. Appl. Phys. Lett. 66, 3618–3620 (1995).
Soreni-Harari, M. et al. Tunning energy level in nanocrystal quantum dots through surface manipulations. Nano Lett. 8, 678–684 (2008).
Coe-Sullivan S., Woo, W.-K., Steckel, J. S., Bawendi, M. & Bulović, V. Tuning the performance of hybrid organic/inorganic quantum dot light-emitting devices. Org. Electron. 4, 123–130 (2003).
Acknowledgements
The authors thank J. Lee, J. M. Lee, J. Chung and I. Song for helpful discussion, S. Jun and H. Jang for providing quantum dots and J. W. Kim, Y. T. Chun, J.-Y. Kwon and Y. G. Lee for fabricating the QD–LED device with the a-Si TFT backplane.
Author information
Authors and Affiliations
Contributions
K.-S.C., E.K.L., W.-J.J. and B.L.C. carried out the experiment and contributed to the writing of the paper. E.J. synthesized the quantum dots. T.-H.K., S.J.L., S.-J.K., J.Y.H. and B.-K.K. assisted with the experiment and the device analysis. J.M.K. contributed to the writing of the paper and the project planning.
Corresponding author
Supplementary information
Supplementary information
Supplementary information (PDF 520 kb)
Rights and permissions
About this article
Cite this article
Cho, KS., Lee, E., Joo, WJ. et al. High-performance crosslinked colloidal quantum-dot light-emitting diodes. Nature Photon 3, 341–345 (2009). https://doi.org/10.1038/nphoton.2009.92
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1038/nphoton.2009.92
This article is cited by
-
Mid-infrared cascade intraband electroluminescence with HgSe–CdSe core–shell colloidal quantum dots
Nature Photonics (2023)
-
Coherent heteroepitaxial growth of I-III-VI2 Ag(In,Ga)S2 colloidal nanocrystals with near-unity quantum yield for use in luminescent solar concentrators
Nature Communications (2023)
-
High-performance all-solution-processed inverted quantum dot light-emitting diodes enabled by water treatment
Nano Research (2023)
-
Ultrahigh-resolution quantum-dot light-emitting diodes
Nature Photonics (2022)
-
Optoelectronic system and device integration for quantum-dot light-emitting diode white lighting with computational design framework
Nature Communications (2022)