Highly Efficient Red-Emitting Hybrid Polymer Light-Emitting Diodes via Forster Resonance Energy Transfer Based on Homogeneous Polymer Blends with the Same Polyfluorene Backbone - Lee, BR; Lee, W; Thanh, LN; Park, JS; Kim, J-S; Kim, JY; Woo, HY; Song, MH (ACS APPLIED MATERIALS & INTERFACES, 2013)