Separating Crystal Growth from Nucleation Enables the In Situ Controllable Synthesis of Nanocrystals for Efficient Perovskite Light-Emitting Diodes

Bibliographische Detailangaben
Veröffentlicht in:	Advanced materials (Deerfield Beach, Fla.). - 1998. - 35(2023), 33 vom: 14. Aug., Seite e2301114
1. Verfasser:	Yu, Wenjin (VerfasserIn)
Weitere Verfasser:	Wei, Mingyang, Tang, Zhenyu, Zou, Hongshuai, Li, Liang, Zou, Yu, Yang, Shuang, Wang, Yunkun, Zhang, Yuqing, Li, Xiangdong, Guo, Haoqing, Wu, Cuncun, Qu, Bo, Gao, Yunan, Lu, Guowei, Wang, Shufeng, Chen, Zhijian, Liu, Zhiwei, Zhou, Huanping, Wei, Bin, Liao, Yingjie, Zhang, Lijun, Li, Yan, Gong, Qihuang, Sargent, Edward H, Xiao, Lixin
Format:	Online-Aufsatz
Sprache:	English
Veröffentlicht:	2023
Zugriff auf das übergeordnete Werk:	Advanced materials (Deerfield Beach, Fla.)
Schlagworte:	Journal Article crystallization in situ controllable synthesis light-emitting diodes nanocrystals perovskites

Beschreibung
Zusammenfassung:	© 2023 Wiley-VCH GmbH. Colloidal perovskite nanocrystals (PNCs) display bright luminescence for light-emitting diode (LED) applications; however, they require post-synthesis ligand exchange that may cause surface degradation and defect formation. In situ-formed PNCs achieve improved surface passivation using a straightforward synthetic approach, but their LED performance at the green wavelength is not yet comparable with that of colloidal PNC devices. Here, it is found that the limitations of in situ-formed PNCs stem from uncontrolled formation kinetics: conventional surface ligands confine perovskite nuclei but fail to delay crystal growth. A bifunctional carboxylic-acid-containing ammonium hydrobromide ligand that separates crystal growth from nucleation is introduced, leading to the formation of quantum-confined PNC solids exhibiting a narrow size distribution. Controlled crystallization is further coupled with defect passivation using deprotonated phosphinates, enabling improvements in photoluminescence quantum yield to near unity. Green LEDs are fabricated with a maximum current efficiency of 109 cd A-1 and an average external quantum efficiency of 22.5% across 25 devices, exceeding the performance of their colloidal PNC-based counterparts. A 45.6 h operating half-time is further documented for an unencapsulated device in N2 with an initial brightness of 100 cd m-2
Beschreibung:	Date Revised 17.08.2023 published: Print-Electronic Citation Status PubMed-not-MEDLINE
ISSN:	1521-4095
DOI:	10.1002/adma.202301114