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Indexed by:期刊论文

Date of Publication:2017-10-01

Journal:DYES AND PIGMENTS

Included Journals:SCIE、EI、Scopus

Volume:145

Page Number:136-143

ISSN No.:0143-7208

Key Words:Cyclometalated Ir(III) complex; Diphenylphosphoryl group; Phosphorescence; Oxygen sensing; Photostability

Abstract:A series of diphenylphosphoryl-substituted bis-cyclometalated Ir(III) complexes (POFIrpic, 4Me-POFIrpic, 5Me-POFIrpic, 5F-POFIrpic and 5CF(3)-POFIrpic) with a picolinic acid as the ancillary ligand have been synthesized and characterized. The influence of substituents (CH3, F, CF3) at the pyridyl moiety of the cyclometalating ligand POFdFppy (2-(2',4'-difluoro-3'-diphenylphosphoryl)phenylpyridine) on the photophysical and electrochemical properties of these Ir(III) complexes has been investigated. These Ir(III) complexes exhibit intense emission bands at 455-492 nm and high phosphorescence quantum yields (Phi(PL)) in a range of 54-64% in CH2Cl2. The phosphorescence oxygen sensing properties of these complexes were studied in solution and in polymer film, and a fast response time and excellent operational stability were observed. Two-site model fitting indicates that 5Me-POFIrpic is the most sensitive oxygen sensing material among the complexes, with a quenching constant K-sv(app) of 0.00793 Torr(-1). Photodegradation tests demonstrate that introduction of a CF3 group into the cyclometalating ligand improves the photostability of the corresponding Ir(III) complex. (C) 2017 Elsevier Ltd. All rights reserved.