Bright light-emitting diodes based on organometal halide perovskite

Tan, Z.-K. et al. (2014) Bright light-emitting diodes based on organometal halide perovskite. Nature Nanotechnology, 9(9), pp. 687-692. (doi: 10.1038/nnano.2014.149) (PMID:25086602)

Abstract

Solid-state light-emitting devices based on direct-bandgap semiconductors have, over the past two decades, been utilized as energy-efficient sources of lighting. However, fabrication of these devices typically relies on expensive high-temperature and high-vacuum processes, rendering them uneconomical for use in large-area displays1,2. Here, we report high-brightness light-emitting diodes based on solution-processed organometal halide perovskites. We demonstrate electroluminescence in the near-infrared, green and red by tuning the halide compositions in the perovskite. In our infrared device, a thin 15 nm layer of CH3NH3PbI3–xClx perovskite emitter is sandwiched between larger-bandgap titanium dioxide (TiO2) and poly(9,9′-dioctylfluorene) (F8) layers, effectively confining electrons and holes in the perovskite layer for radiative recombination. We report an infrared radiance of 13.2 W sr−1 m−2 at a current density of 363 mA cm−2, with highest external and internal quantum efficiencies of 0.76% and 3.4%, respectively. In our green light-emitting device with an ITO/PEDOT:PSS/CH3NH3PbBr3/F8/Ca/Ag structure, we achieved a luminance of 364 cd m−2 at a current density of 123 mA cm−2, giving external and internal quantum efficiencies of 0.1% and 0.4%, respectively. We show, using photoluminescence studies, that radiative bimolecular recombination is dominant at higher excitation densities. Hence, the quantum efficiencies of the perovskite light-emitting diodes increase at higher current densities. This demonstration of effective perovskite electroluminescence offers scope for developing this unique class of materials into efficient and colour-tunable light emitters for low-cost display, lighting and optical communication applications.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Docampo, Dr Pablo
• Authors: Tan, Z.-K., Moghaddam, R. S., Lai, M. L., Docampo, P., Higler, R., Deschler, F., Price, M., Sadhanala, A., Pazos, L. M., Credgington, D., Hanusch, F., Bein, T., Snaith, H. J., and Friend, R. H.
• College/School: College of Science and Engineering > School of Chemistry
• Journal Name: Nature Nanotechnology
• Publisher: Nature Publishing Group
• ISSN: 1748-3387
• ISSN (Online): 1748-3387
• Published Online: 03 August 2014