Ultrafast Dynamics of Triplet Excitons in Alq_3-Bridge-Pt(Ⅱ)porphyrin Electroluminescent Materials

摘要

Achieving control over the dynamics and migration of excited states is crucial for maximizing the performance of both small-molecule- and polymer-based organic light-emitting diodes (OLEDs). Since triplets and singlets are generated by electron-hole recombination in a 3:1 ratio, utilizing triplet excited states in radiative processes is of utmost importance and the ability to harvest the energy of triplet excited states is important for obtaining the maximum light output in OLEDs. The triplet energy of organic hosts (donor, D) may be harvested by a phosphorescent dopant acceptor (A) dispersed in a host. While the dispersion of a dopant in a host is easy to do, potential phase separation during deposition may result in uneven distribution of the donor—acceptor (D-A) distances and diminished light output from the device.