Highly Efficient Light-Emitting Diodes of Colloidal Metal-Halide Perovskite Nanocrystals beyond Quantum Size
SCIE
SCOPUS
- Title
- Highly Efficient Light-Emitting Diodes of Colloidal Metal-Halide Perovskite Nanocrystals beyond Quantum Size
- Authors
- Kim, Young-Hoon; Wof, Christoph; Kim, Young-Tae; Cho, Himchan; Kwon, Woosung; Do, Sungan; Sadhanala, Aditya; Park, Chan Gyung; RHEE, SHI WOO; Im, Sang Hyuk; Friend, Richard H.; Leet, Tae-Woo
- Date Issued
- 2017-07
- Publisher
- AMER CHEMICAL SOC
- Abstract
- Colloidal metal-halide perovskite quantum dots (QDs) with a dimension less than the exciton Bohr diameter D-B (quantum size regime) emerged as promising light emitters due to their spectrally narrow light, facile color tuning, and high photoluminescence quantum efficiency (PLQE). However, their size-sensitive emission wavelength and color purity and low electroluminescence efficiency are still challenging aspects. Here, we demonstrate highly efficient light-emitting diodes (LEDs) based on the colloidal perovskite nano crystals (NCs) in a dimension > D-B (regime beyond quantum size) by using a multifunctional buffer hole injection layer (Buf-HIL). The perovskite NCs with a dimension greater than D-B show a size-irrespective high color purity and PLQE by managing the recombination of excitons occurring at surface traps and inside the NCs. The Buf-HIL composed of poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS) and per fluorinated ionomer induces uniform perovskite particle films with complete film coverage and prevents exciton quenching at the PEDOT:PSS/perovskite particle film interface. With these strategies, we achieved a very high PLQE (similar to 60.5%) in compact perovskite particle films without any complex post-treatments and multilayers and a high current efficiency of 15.5 cd/A in the LEDs of colloidal perovskite NCs, even in a simplified structure, which is the highest efficiency to date in green LEDs that use colloidal organic-inorganic metal-halide perovskite nanoparticles including perovskite QDs and NCs. These results can help to guide development of various light-emitting optoelectronic applications based on perovskite NCs.
- Keywords
- EXCITON BINDING-ENERGY; SOLAR-CELLS; NANOPARTICLES; CRYSTALLIZATION; DEVICES; BRIGHT
- URI
- https://oasis.postech.ac.kr/handle/2014.oak/92082
- DOI
- 10.1021/acsnano.6b07617
- ISSN
- 1936-0851
- Article Type
- Article
- Citation
- ACS Nano, vol. 11, no. 7, page. 6586 - 6593, 2017-07
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- There are no files associated with this item.
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