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luminous lifetimes and smaller voltage increases than the Alq
reference device. This study is the first report of 2H-1,2,3-triazole
as an OLED material, and we clearly demonstrated that bipyr-
idine-substituted benzo[1,2,3]triazoles, which are derivatives of
2H-1,2,3-triazole, must be useful as ETMs for OLEDs.
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Acknowledgements
The authors would like to thank Prof. Dr M. Kimura for mass
spectroscopic measurements. The authors would like to thank
Riken Keiki and Rigaku for Ip and density measurements.
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