Efficient Polymer White‐Light‐Emitting Devices for Solid‐State Lighting

High-efficiency conjugated-polymer-hosted blue phosphorescent light-emitting diodes

“…Non-conjugated polymer poly(N-vinylcarbazole) (PVK) has been a commonly used polymer host for phosphorescent dyes [9][10][11][12]. As a host polymer, PVK has however an inherent defect in that its electron and hole mobility difference is too large.…”

Cyclometalated Ir(III) Complexes for High-Efficiency Solution-Processable Blue PhOLEDs

“…The advantages of solution processing over thermal evaporation have been widely recognized. 16,17,18,19,20 To address these issues we have explored systematic functionalization of the ppy ligands of is straightforward to synthesise and has been obtained in >1 g batches. mmol) in 1,2-dimethoxyethane (20 mL) was degassed by bubbling argon through the mixture for 15 min.…”

High‐Performance All‐Polymer White‐Light‐Emitting Diodes Using Polyfluorene Containing Phosphonate Groups as an Efficient Electron‐Injection Layer

“…The brightness of the PWLED reaches 1000, 10000 and 46830 cd m − 2 at driving voltages of 4.5, 5.4, and 7.5 V, respectively. The peak external quantum effi ciency ( EQE ), the forward viewing LE and PE reach 6 …”

“…Currently, the common strategy in fabrication of PWLEDs is to use multi-component blends as white emissive layer (EML), including either two-(blue and yellow) or three-color (blue, green and red) polymer-blend system [ 2 , 3 ] and polymer-host/ small-molecule-dopant (fl uorescent or phosphorescent) system. [4][5][6] However, these systems suffer from intrinsic phase separation, resulting in rapid effi ciency roll-off at high brightness and unstable emission spectra. [ 7 ] The simultaneous requirements of high-effi ciency, especially at high brightness, and stable emission spectra of white devices for their applications render the PWLEDs based on white single polymer (WSP) a preferable alternative because they inherently exclude phase separation limitation and potentially possess higher light-emitting effi ciencies and better color stability.…”