Instant low-temperature cross-linking of poly(N-vinylcarbazole) for solution-processed multilayer blue phosphorescent organic light-emitting devices

Poly(N-vinylcarbazole) undergoes cross-linking to highly solvent-resistant films through an oxidative coupling reaction, for which an annealing process takes only 3 min at 110 °C. This reaction allows the construction of a solution-processed multilayer OLED without a time-consuming annealing process. The maximum external quantum efficiency reaches 18%, and remains at 17%, even at a high brightness of 10 000 cd m(-2) for all-solution-processed blue OLEDs.