title: Toward highly efficient blue organic light-emitting diodes: fabricating a good-quality emissive layer cast from suitable solvents.
abstract: Spin-cast from various solvents, emissive layers show different film morphologies and performances in solution-processed organic light-emitting diodes (OLEDs). Here we fabricated and demonstrated highly efficient blue OLEDs based on bis[3,5-difluoro-2-(2-pyridyl)phenyl]-(2-carboxypyridy)iridium(iii) by choosing several kinds of solvents for spin-coating. Experiments indicate that the single-layer device with an emissive film cast from chlorobenzene shows its best performance with a highest current efficiency of 18.99 cd A(-1), a maximum luminance of 20.5 × 10(3) cd m(-2) and an emission band centered at 474 nm. The efficiency achieved is the highest reported for solution-processed simple-manufactured OLEDs doped with transition metal phosphors emitting in the blue region.
authors.affiliation: Key Lab of Organic Optoelectronics and Molecular Engineering of Ministry of Education, Department of Chemistry, Tsinghua University, Beijing 100084, P. R. China. duanl@mail.tsinghua.edu.cn qiuy@mail.tsinghua.edu.cn.
authors.forename: Dongxin
authors.initials: D
authors.lastname: Ma
authors.forename: Lian
authors.initials: L
authors.lastname: Duan
authors.forename: Yong
authors.initials: Y
authors.lastname: Qiu