Incorporation of electroluminescence and electrochemiluminescence in one organic light-emitting device

Abstract

The incorporation of electroluminescence and electrochemiluminescence in one light-emitting device with the configuration of indium tin oxide (ITO)/[Ru(bpy)2(dimbpy)](PF6)2∕Alq3(30nm)∕NPB(45nm)∕Ag(60nm) is investigated. When the ITO and Ag electrodes are negatively and positively biased respectively, the color of the emission changes from green to light yellow-white within 100 s. So there is only one recombination zone in the bulk of the Alq3 at the initial stage of the operation, followed by the formation of another recombination zone in the bulk of the [Ru(bpy)2(dimbpy)](PF6)2. This directly indicates the existence of unipolar injection (electron injection) process in the ruthenium complex layer. The external quantum efficiency of the device is 1.4% compared with 0.45% of the ITO∕[Ru(bpy)2(dimbpy)](PF6)2∕Ag device, improved by twofold. Furthermore, this hybrid device provides a feasible way to control the emission of a wide spectrum of colors including red, green, yellow, and white.

Electroluminescent devices from ionic transition metal complexes

“…A number of groups have also investigated incorporating iTMCs into multilayered OLED structures. Voltage-controlled colour tuning has been achieved by Zhen et al 45 and Wang et al, 58 using a hybrid OLED/LEC multilayered cell. By introducing a 30 nm spun-cast [Ru(bpy) 3 ] 2+ (PF 6…”

Electrochemiluminescent Systems as Devices and Sensors

“…Particularly, the incorporation of electroluminescence and electrochemiluminescence in one light-emitting device may be a new way to improve the efficiency of light-emitting devices. 213 Another interesting aspect of such hybrid-emitting cells is an easy way for color manipulation that may result in practical applications as signaling devices.…”

Opto-electrical properties of single layer flexible electroluminescence device with ruthenium complex

“…The linear fit gives an efficiency g L of 0.0024 cd/A for a brightness of a few cd/m 2 . This value is relatively small when compared to similar LECs fabricated on glass substrate, where values near 200-500 cd/m 2 are currently reported in the literature [2,3,6,[15][16][17][18] and also obtained by ourselves. In other hand, no much work using ruthenium complexes as emissive materials on flexible substrates has been reported.…”

“…As found for rhenium(I) complexes, the electroluminescence (EL) of these materials follows a very complex process, which involves a hopping of oxidized and reduced ions [5,6]. In particular, in the case of ruthenium complexes, and upon an applied voltage at the electrodes, the [RuII(L) 3 ] 2+ (where L is the organic ligand) is oxidized at the anode into [RuIII(L) 3 ] 3+ and reduced at the cathode into [RuII(L * À )(L) 2 ] + .…”