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 Förster or Dexter energy transfer is analyzed through time resolved photoluminescence. 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).
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Apr 10, 2017
- Source ID
- 10.1002/adma.201606859
Entities
People
- En‐ping Yao
- Lei Meng
- Pengyu Sun
- Shiqi Dong
- Yang Yang
- Ye Yang
- Zhanlue Yang
Organizations
- Air Force Office of Scientific Research
- National Cheng Kung University
- National Science Foundation
- University of California, Los Angeles