A polymer blend approach to fabricating the hole transport layer for polymer light-emitting diodes

This contribution describes an approach to fabricating high-efficiency hole-transport layers (HTLs) for polymer light-emitting diodes (PLEDs). HTLs fabricated by this approach have two components: a siloxane-derivatized, crosslinkable, hole-transporting material and a hole-transporting polymer. These HTLs exhibit high transparency, have no corrosive effects on the indium tin oxide anode, and have minimal pixel “cross-talk” potential. PLEDs that are fabricated using these HTLs exhibit superior performance (40% greater maximum current efficiency) versus analogous devices using a conventional poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS) HTL. Most importantly, this approach has considerable flexibility and can be applied as a general strategy to manipulate energy level alignments in PLEDs.