Reducing Architecture Limitations for Efficient Blue Perovskite Light‐Emitting Diodes. Issue 20 (25th March 2018)

• Record Type: Journal Article
• Authors: Gangishetty, Mahesh K.; Hou, Shaocong; Quan, Qimin; Congreve, Daniel N.
• Is Part Of: Advanced materials. Volume 30:Issue 20(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-03-25
• Subjects: blue LEDs -- device architecture -- perovskite LEDs; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201706226
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Light‐emitting diodes utilizing perovskite nanocrystals have generated strong interest in the past several years, with green and red devices showing high efficiencies. Blue devices, however, have lagged significantly behind. Here, it is shown that the device architecture plays a key role in this lag and that NiO x, a transport layer in one of the highest efficiency devices to date, causes a significant reduction in perovskite luminescence lifetime. An alternate transport layer structure which maintains robust nanocrystal emission is proposed. Devices with this architecture show external quantum efficiencies of 0.50% at 469 nm, seven times higher than state‐of‐the‐art devices at that wavelength. Finally, it is demonstrated that this architecture enables efficient devices across the entire blue‐green portion of the spectrum. The improvements demonstrated here open the door to efficient blue perovskite light‐emitting diodes. Abstract : Blue perovskite light‐emitting diodes have lagged significantly behind red and green ones. It is shown that the device architecture plays a key role. An alternate structure maintains robust perovskite emission, and devices with this architecture show external quantum efficiencies of 0.50% at 469 nm, enabling efficient devices across the entire blue‐green portion of the spectrum.