A quick operating organic EL device using Ru complex light-emitting layer with 2,5-bis(4-tert-butyl-2-benz-oxazolyl) thiophene electron transport layer
S. Shiratori, A quick operating organic EL device using Ru complex light-emitting layer with 2,5-bis(4-tert-butyl-2-benz-oxazolyl) thiophene electron transport layer, MAT SCI E B, 85(2-3), 2001, pp. 149-153
Recently, solid-state light-emitting devices based on small molecules such
as Ru(bpy)(3)(PF6)(2) and its derivatives attracted attention as electro lu
minescence (EL) materials because the luminance shows as high as 1600 cd m(
-2) at only 5 V with spin-cast films in air without sealing the devices. De
vices based on these materials operate at low voltage (2.5-5 V), however, r
esponse of light emission after applying voltage is rather slow, suggesting
a similar mechanism with liquid electro-generated chemiluminescence (ECL)
cells. In this paper, we added thin electron transporting layer, 2,5-bis(5-
tert-butyl-2-benz-oxazolyl) thiophene (BBOT) film (ca. 200 nm) between Ru c
omplex light-emitting layer and A1 electrode. As a result, much quicker res
ponse was achieved than the ruthenium(II) complex EL devices without adding
the BBOT electron transporting layer. (C) 2001 Elsevier Science B.V. All r
ights reserved.