Microporous polymer films for enhancing light extraction of white-light organic light-emitting diodes

摘要

In this study, a new, facile, and low-cost approach was proposed to fabricate microporous polymer thin films (MPFs) for enhancing the light extraction of white-light organic light-emitting diodes (WLOLED). MPFs were fabricated by blending polymers with starch particles, spin-coating the blended polymer to a polyethylene terephthalate (PET) substrate, and then removing starch particles through an acid hydrolysis process. The final product was attached to the rear of the glass substrate of a WLOLED. MPF structures scattered emitted photons inside the OLED device and reduced light trapped in the substrate mode. Therefore, the maximum outcoupling efficiency improvement was 49%; approximately 69% of the substrate-mode light was extracted; and the color rendering index of the WLOLED was higher than that of the device without MPF. MPFs with a large area ( 20 x 20 cm(2)) can be easily fabricated through the proposed method.