Highly Efficient Heteroleptic Cerium(III) Complexes with a Substituted Pyrazole Ancillary Ligand and Their Application in Blue Organic Light-Emitting Diodes

Autor:	Hao Qi, Liding Wang, Peiyu Fang, Wenchao Yan, Ge Zhan, Zuqiang Bian, Zhiwei Liu
Rok vydání:	2021
Předmět:	Photoluminescence Chemistry Ligand Quantum yield chemistry.chemical_element Pyrazole Inorganic Chemistry chemistry.chemical_compound Cerium OLED Physical chemistry Quantum efficiency Physical and Theoretical Chemistry Luminescence
Zdroj:	Inorganic Chemistry. 60:18103-18111
ISSN:	1520-510X 0020-1669
DOI:	10.1021/acs.inorgchem.1c02711
Popis:	Compared with red and green organic light-emitting diodes (OLEDs), blue is the bottleneck that restricts the wide development of OLEDs from being the next-generation technology for displays and lighting. As a new type of emitter, a Ce(III) complex shows many satisfactory advantages, such as a short excited-state lifetime, 100% theoretical exciton utilization efficiency, and tunable emission color. Herein we synthesized three heteroleptic Ce(III) complexes Ce(TpMe2)2(dtfpz), Ce(TpMe2)2(dmpz), and Ce(TpMe2)2(dppz) with the hydrotris(3,5-dimethylpyrazolyl)borate (TpMe2) main ligand and different substituted pyrazole ancillary ligands, namely, 3,5-di(trifluomethyl)pyrazolyl (dtfpz), 3,5-dimethylpyrazolyl (dmpz), and 3,5-diphenylpyrazolyl (dppz), and studied their structures and luminescence properties. All the Ce(III) complexes exhibited a near-unity photoluminescence quantum yield both in solution and as a powder with maximum emission wavelengths in the range of 450-486 nm. The OLED employing Ce(TpMe2)2(dppz) as the emitter showed the best performance, including a turn-on voltage, maximum luminance, and external quantum efficiency of 3.2 V, 29 200 cd m-2, and 12.5%, respectively.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::fee1e165f81ea447a655b69e21d8097f https://doi.org/10.1021/acs.inorgchem.1c02711 Zobrazit plný text záznamu