Two‐Color Strip‐Patterned White OLEDs: Tunable Color‐Temperature via Pattern Dimension Control

Abstract

White light is attained by combining different‐colored emissions. White organic light‐emitting diodes, therefore, should be fabricated to obtain mixed emissions from different organic luminophores while suppressing energy transfer between each other. Here, the authors present a simple means to realize this goal by forming two‐color strip‐patterns of light‐emitting polymer (orange) and an iridium complex (sky‐blue) luminophores entirely through solution processes. The formation of the two‐color patterns is facilitated by i) the use of a highly efficient crosslinker permitting the construction of structurally robust orange primary strip‐patterns and ii) the contrast in the surface energy allowing selective wetting of the secondary sky‐blue patterns between the orange primary patterns. The emissive layer comprising the two‐color strip ‐patterns allows for the mixing ratio of the two colors to be adjusted by simply varying the areal ratio of the two patterns, which in turn, controls the white emission color‐temperature from 2119 to 7994 K.

P - and N -type InAs nanocrystals with innately controlled semiconductor polarity

“…For the solid-state ligand-exchange step, EDT (98%, Sigma-Aldrich), ammonium chloride (NH 4 Cl, 99.5%, Sigma-Aldrich), ammonium bromide (NH 4 Br, 99%, Sigma-Aldrich), ammonium iodide (NH 4 I, 99%, Sigma-Aldrich), sodium sulfide (Na 2 S, Sigma-Aldrich), acetonitrile (electronic grade, 99.999%, Sigma-Aldrich), and methanol (anhydrous, 99.8%) were used without further purification. The 6-LiXers were synthesized according to a previously reported method ( 52 , 53 ). For FETs, Si wafers ( n ++ , <0.005 ohm) with a thermally grown SiO 2 layer (300 nm) (Namkang Hi-Tech) were used as the substrate.…”

Thiazolo[5,4-d]thiazoles with a spirobifluorene moiety as novel D–π–A type organic hosts: design, synthesis, structure–property relationship and applications in electroluminescent devices

“…26 In contrast to well-known organometallic emitters, 27 the structural diversity of the already described electron-rich (D) and electron-deficient (A) scaffolds means that there is no generality in a structural design towards organic SMs as bipolar hosts in emissive layers of EL devices. The research has been concentrated on achievements of a white light emission 28,29 either by combining two primary colours (blue and orange) or by merging three complementary colours (red, green, and blue). 30–32 The possibility to achieve a yellow emission through structural manipulation remains lacking despite its importance.…”