Sprayed Organic Electrophosphorescent Devices with Small Organic Molecules

Sprayed organic electrophosphorescent devices with small organic molecules have been investigated. By heating the entire spray system, i.e., a spray gun and a glass substrate, a high device performance without leakage current has been realized. Using the green electrophosphorescent molecule fac tris(2-phenyl-pyridine)iridium Ir(ppy)₃ as a doped material, device performance with a maximum luminance of 18,400 cd/m², a maximum luminous power efficiency of 20.9 lm/W, and a maximum quantum efficiency of 16.9% could be obtained. By mixing blue and red electrophosphorescent molecules of iridium(III) bis(2-(4,6-difluorophenyl) pyridinato-N,C2') picolinate (FIrpic) and iridium(III) bis(2-(2'-benzothienyl) pyridinato-N,C3') (acetylacetonate) (Btp₂Ir(acac)), white emission with Commission Internationale d'Eclairage chromaticity coordinates of (0.33, 0.34) is also achieved.