Mechanochemically interlocked cubane copper complex interface for WOLED

Abstract

In the rapid development of organic light-emitting diodes (OLEDs), phosphorescent transition metal complexes have played a crucial role as the most promising candidates for next generation display and lighting applications. However, most devices are fabricated using iridium and platinum-based complexes which are expensive and available in very limited quantities, whereas using relatively abundant organometallic complexes for fabrication results mostly in inefficient performance results. To overcome these issues, we have synthesized tetra copper iodide with tetra triphenyl cage like structure (denoted as CIPh) as an emerging class of luminescent material by mechanochemical grinding followed by thermal treatment for application in white OLED. The CIPh complex exhibits considerable quantum yield and a millisecond decay lifetime. Phosphorescent OLEDs were fabricated using CIPh complex as emitter shows a remarkable performance with external quantum efficiency and current efficiency of 5.28 % and 22.76 cd/A, with a high brightness of 4200 cd m−2, respectively. White OLEDs were also fabricated with a fluorescent blue and phosphorescent red emitted with (CIPh) as green emitter and achieved an impressive CRI of 82 with an EQE of over 3 %. This is the first ever attempt at fabricating WOLEDs using organocopper complex.