High performance hybrid white OLEDs based on new platinum complexes and new blue fluorescence host Anurach Poloek, a,b,c Chieh Wang, b,d Chiao-Wen Lin, b Chin-Ti Chen,* b and Chao-Tsen Chen,* a a Department of Chemistry, National Taiwan University, Taipei, Taiwan 10617, R. O. C. b Institute of Chemistry, Academia Sinica, Taipei, Taiwan 11529, R. O. C. c Nano Science and Technology Program, TIGP, Academia Sinica, Taipei, Taiwan 11529, R. O. C. d Department of Chemistry, National Chiao Tung University, Hsinchu, Taiwan 300, R.O.C. ABSTRACT A new series of platinum complexes containing 4-hydroxy-1,5-naphtyridine derivative with different substitutens such as methyl, dimethyl, phenyl, phenoxy, dimethyl amine, piperidine, morpholine, phenoxazine or carbazole unit as the primary ligand and 2-(2,4-difluorophenyl)pyridine as the secondary ligand were synthesized and characterized. Single crystal X-ray diffraction studies of FPtOPhND, FPtCzND and FPtdmaND showed trans-coordinated in distorted square-planar geometry. Their photophysical properties and electrochemical properties were examined. All platinum complexes in these series exhibited dual emissions not only in solution but also in solid state thin film. Employing CBP or 4P-NPD as host material, high efficiency monochromatic and high quality hybrid white organic light emitting diodes (WOLEDs) were achieved with the single platinum complex dopant device, a relatively simple device configuration. Keywords: hybrid white OLEDs, platinum complex, high CRI, phosphorescence. 1. INTRODUCTION In the past few decades, white organic light-emitting diodes (WOLEDs) have drawn increasing attention because of their potential applications in full color flat-panel displays and solid-state lighting. 1,2 In order to achieve white light emission, two or three emitters are generally required in device configuration. Particularly, three phosphorescent dopants (red, green, blue) have been employed to realize high efficiency and high quality WOLEDs. 3,4 Nonetheless, such a strategy leads to the complicated structure and difficulty getting of color balance. In addition, blue phosphorescent emitters still suffer from the lack of stability. To simplify WOLED fabrication, utilizing only two complementary phosphorescent emitters, either blue and yellow or blue and orange, 5-8 is a reasonable alternative to achieve white EL. In order to achieve stable WOLEDs and yet having easy fabrication, fluorescence (F)-phosphorescence (P) hybrid WOLEDs have been demonstrated before. 9 Recently, the hybrid of blue fluorescence and yellow 10,11 or orange 12,13 phosphorescence has attracted much attention in generating white EL with long stability and simplified device structure. However, most of such hybrid WOLEDs have been based on iridium complex phosphorescent dopant. Although F-P hybrid WOLEDs with iridium complexes exhibit relatively high EL efficiency, insufficient CRI less than 80 is always the results. To improve the quality (i.e., CRI) of F-P hybrid WOLED with a simple device configuration, platinum complex is a better choice than iridium complex because square planar molecule geometry of platinum complex can facilitate molecular aggregate and excimer formation that exhibits red-shifted emission different from the complex itself. Such emission feature of platinum complex easily broadens the EL spectra and high quality virtual sunlight often can be achieved. Herein, we report the synthesis, and characterization, as well as photophysical and electrochemical properties of a new series of heteroleptic platinum complexes bearing 4-hydroxy-1,5-napthyridine derivatives 14 and 2-(2,4- difluorophenyl)pyridine (F) 15 as the mixed ligand (Figure 1). With conventional 4,4'-N,N′-dicarbazolebiphenyl (CBP) or the new 4P-NPD as the host material, application of FPtXND for OLEDs showing monochromatic color or hybrid white EL has been extensively explored. *Correspondence: Email: chintchen@gate.sinica.edu.tw ; Tel: +886-2-2789-8542; Fax: +88-2-2783-1237 Invited Paper Organic Light Emitting Materials and Devices XVIII, edited by Franky So, Proc. of SPIE Vol. 9183, 91831F © 2014 SPIE · CCC code: 0277-786X/14/$18 · doi: 10.1117/12.2060371 Proc. of SPIE Vol. 9183 91831F-1