Multilayer white polymer light-emitting diodes with deoxyribonucleic acid-cetyltrimetylammonium complex as a hole-transporting/electron-blocking layer

Using a thin film of deoxyribonucleic acid-cetyltrimetylammonium (DNA-CTMA) complex as a hole-transporting/electron-blocking layer, we have developed a sequential solution-processing approach for constructing multilayer (up to five layers) white polymer light-emitting diodes, incorporating the poly(9,9-dioctylfluorene-2,7-diyl)/poly[2-methoxy-5(2'-ethyl-hexyloxy)-1, 4-phenylene vinylene] emissive layer. These devices were demonstrated to show a low turn-on voltage (similar to 5 V), high efficiency (10.0 cd/A), and high brightness (10500 cd/m(2)) with an improved white-color stability. (C) 2008 American Institute of Physics.