White Organic Light Emitting Device with Dyestuff DCJTB Blended in Polymer

The Alq3 and DCJTB were blended with poly(N-vinylcarbazole)(PVK)in different weight ratios and spin coated into films.Multilayer devices with the light emitting layer PVK∶ Alq3:DCJTB were fabricated,and their structure was ITO/PVK∶Alq3∶DCJTB/BCP/Alq3/LiF/Al in which BCP and Alq3 were employed as the hole-blocking and electron-transporting layers respectively,PVK is the blue light-emitting as well as hole-transporting layer.The mass proportion of PVK relative to Alq3 was tuned while the quality ratio of PVK to DCJTB remained(100∶1).Finally,fairly pure and stabile white emission was achieved when PVK∶Alq3∶DCJTB was 100∶5∶1.The CIE coordinate was(0.33,0.36)at 14 V,which is very stable at various biases(10-14 V).