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Title: High-Brightness Blue and White LEDs based on Inorganic Perovskite Nanocrystals and their Composites

Abstract

Inorganic metal halide perovskite nanocrystals (NCs) have been employed universally in light-emitting applications during the past two years. Here, blue-emission (≈ 470 nm) Cs-based perovskite NCs are derived by directly mixing synthesized bromide and chloride nanocrystals with a weight ratio of 2:1. High-brightness blue perovskite light-emitting diodes (PeLEDs) are obtained by controlling the grain size of the perovskite films. Moreover, a white PeLED is demonstrated for the first time by blending orange polymer materials with the blue perovskite nanocrystals as the active layer. Exciton transfer from the blue nanocrystals to the orange polymers via Forster or Dexter energy transfer is analyzed through time resolved photoluminescence. In conclusion, by tuning the ratio between the perovskite nanocrystals and polymers, pure white light is achieved with the a CIE coordinate at (0.33,0.34).

Authors:
 [1];  [2];  [2];  [2];  [2];  [3];  [2]
  1. Univ. of California, Los Angeles, CA (United States); National Cheng Kung Univ., Tainan (Taiwan)
  2. Univ. of California, Los Angeles, CA (United States)
  3. National Renewable Energy Lab. (NREL), Golden, CO (United States)
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
US Air Force Office of Scientific Research (AFOSR); National Science Foundation (NSF); USDOE
OSTI Identifier:
1364159
Report Number(s):
NREL/JA-5900-68405
Journal ID: ISSN 0935-9648
Grant/Contract Number:
AC36-08GO28308
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Advanced Materials
Additional Journal Information:
Journal Volume: 29; Journal Issue: 23; Journal ID: ISSN 0935-9648
Publisher:
Wiley
Country of Publication:
United States
Language:
English
Subject:
14 SOLAR ENERGY; 36 MATERIALS SCIENCE; light-emitting diodes; nanocrystals; perovskites; white light

Citation Formats

Yao, En -Ping, Yang, Zhanlue, Meng, Lei, Sun, Pengyu, Dong, Shiqi, Yang, Ye, and Yang, Yang. High-Brightness Blue and White LEDs based on Inorganic Perovskite Nanocrystals and their Composites. United States: N. p., 2017. Web. doi:10.1002/adma.201606859.
Yao, En -Ping, Yang, Zhanlue, Meng, Lei, Sun, Pengyu, Dong, Shiqi, Yang, Ye, & Yang, Yang. High-Brightness Blue and White LEDs based on Inorganic Perovskite Nanocrystals and their Composites. United States. doi:10.1002/adma.201606859.
Yao, En -Ping, Yang, Zhanlue, Meng, Lei, Sun, Pengyu, Dong, Shiqi, Yang, Ye, and Yang, Yang. Mon . "High-Brightness Blue and White LEDs based on Inorganic Perovskite Nanocrystals and their Composites". United States. doi:10.1002/adma.201606859. https://www.osti.gov/servlets/purl/1364159.
@article{osti_1364159,
title = {High-Brightness Blue and White LEDs based on Inorganic Perovskite Nanocrystals and their Composites},
author = {Yao, En -Ping and Yang, Zhanlue and Meng, Lei and Sun, Pengyu and Dong, Shiqi and Yang, Ye and Yang, Yang},
abstractNote = {Inorganic metal halide perovskite nanocrystals (NCs) have been employed universally in light-emitting applications during the past two years. Here, blue-emission (≈ 470 nm) Cs-based perovskite NCs are derived by directly mixing synthesized bromide and chloride nanocrystals with a weight ratio of 2:1. High-brightness blue perovskite light-emitting diodes (PeLEDs) are obtained by controlling the grain size of the perovskite films. Moreover, a white PeLED is demonstrated for the first time by blending orange polymer materials with the blue perovskite nanocrystals as the active layer. Exciton transfer from the blue nanocrystals to the orange polymers via Forster or Dexter energy transfer is analyzed through time resolved photoluminescence. In conclusion, by tuning the ratio between the perovskite nanocrystals and polymers, pure white light is achieved with the a CIE coordinate at (0.33,0.34).},
doi = {10.1002/adma.201606859},
journal = {Advanced Materials},
number = 23,
volume = 29,
place = {United States},
year = {Mon Apr 10 00:00:00 EDT 2017},
month = {Mon Apr 10 00:00:00 EDT 2017}
}

Journal Article:
Free Publicly Available Full Text
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Cited by: 8works
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