White light-emitting devices based on the combined emission from red CdSe/ZnS quantum dots, green phosphorescent, and blue fluorescent organic molecules

We report on a white hybrid light-emitting device realized by combining red emission from CdSe/ZnS quantum dots (QDs), green emission from a phosphorescent organic complex tris[2-4(4-toltyl)phenylpyridine]iridium [Ir(mppy)(3)], and blue emission from a fluorescent organic emitter 2,2('),7,7(')-tetrakis(2,2-diphenylvinyl)spiro-9,9(')-bifluorene. Energy transfer processes from the organic components to the QDs have been analyzed versus the Ir(mppy)(3) concentration in order to optimize the device performances. A maximum external quantum efficiency of 2.1%, corresponding to a power efficiency of 2.2 lm/W at 13 mA/cm(2), and a color rendering index of 89.8 at 10 200 cd/m(2) were achieved.