Tuning Color of Charged Iridium (III) Complexes with a Spiro N,N'-Bidentate Ligand

Abstract:

Organic light emitting diodes (OLEDs), charged iridium(III) complexes, spiro ligand Abstract. We report the synthesis, characterization and photophysical properties of a cationic cyclometalated Ir(III) complexes of general formula [Ir(ppy)2(spbpy)]⁺Cl, [Ir(diFppy)₂(spbpy)]⁺Cl^ and [Ir(thiopy)2(spbpy)]⁺Cl where ppy, spbpy, diFppy and thiopy are 2-phenylpyridine, 4,5-diaza-9,9′-spirobifluorene, 2-(2′,4′-difluorophenyl)-pyridine and 2-(thiophen-2′-yl)-pyridine, respectively. The complexes exhibit strong absorption bands in the UV region in solution spectra, due to spin-allowed ligand-centred (LC) and weaker absorption bands at longer wavelengths from metal-to-ligand charge transfer (MLCT). The photoluminescence spectra of all the complexes were characterised by a combination of 3MLCT and ³π→π^* states. The emission color of a cationic cyclometalated Ir(III) complexes in solution have successfully tuned from green to orange (501-582 nm).

• Periodical: Applied Mechanics and Materials (Volumes 229-231)
• Pages: 192-196
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.229-231.192
• Online since: November 2012
• Authors: Kattaliya Mothajit, Kittiya Wongkhan, Rukkiat Jitchati
• Keywords: Charged Iridium (III) Complexes, Organic Light Emitting Diodes (OLEDs), Spiro ligand

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