All-Solution-Processed Multilayered Small-Molecule OLEDs with High Device Efficiency

Abstract

All-solution-processed multilayer blue small molecular organic light-emitting diodes are fabri-cated by blade coating method. Fluorescent blue host,1-(7-(9,9'-bianthracen-10-yl)- 9,9-dioctyl-9H-fluoren-2-yl)pyrene, and blue dopant, 4,4'-(IE,I'E)-2,2'(naphthalene-2,6-diyl)bis(ethene-2,1-diyl)bis(N,N-bis(4-hexylphenyl)aniline), are synthesized to achieve good solubility and pinhole free thin film by solution process. The multilayer device structure with holelelectron transport layer is achieved by blade coating method without the dissolution problem between layers. The efficiency of the all-solution-processed device is 4.8 cd/A at 1,200 cd/m(2), close to that by thermal deposition in high vacuum chamber.