Efficient Deep Blue Platinum Acetylide Phosphors with Acyclic Diaminocarbene Ligands
Yanyu Wu, Zhili Wen, Judy I. Wu, Thomas S. Teets
Abstract
Abstract Here we report five blue‐phosphorescent platinum bis‐phenylacetylide complexes with an investigation of their photophysical and electrochemical attributes. Three of the complexes ( 1 – 3 ) are of the general formula cis ‐Pt(CNR) 2 (C≡CPh) 2 , in which CNR is a variably substituted isocyanide and C≡CPh is phenylacetylide. These isocyanide complexes serve as precursors for complexes of the general formula cis ‐Pt(CNR)(ADC)(C≡CPh) 2 ( 4 and 5 ), in which ADC is an acyclic diaminocarbene installed by amine nucleophilic addition to one of the isocyanides. All of the complexes exhibit deep blue phosphorescence with λ max ∼430 nm in poly(methyl methacrylate) (PMMA) thin films. Whereas isocyanide complexes 1 – 3 exhibit modest photoluminescence quantum yields ( Φ PL ), incorporation of one acyclic diaminocarbene ligand results in a three‐fold to 16‐fold increase in Φ PL while still maintaining an identical deep blue color profile.