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We report the synthesis of a tris-cyclometalated iridium complex which emits sky-blue light and its potential use in phosphorescent light-emitting devices. The hybrid meso-structured nanocomposites by sol-gel co-assembly with tetraethyl ortho-silicate and corresponding molecular interactions within mesopores were also demonstrated. Electroluminescent devices were fabricated using carbazole-based monomers and iridium complex as the active layer, acting as a host/guest system through a co-assembled sol-gel process. Devices based on this nanocomposite showed improved luminescent efficiencies several times higher than that of similar chromophores elaborated in the literature. A triple-layer electroluminescence device with the configuration of ITO/PEDOT/ Ir(F2OC11ppy)(3):CA-C11:PBD nanocomposite/TPBI/Ca/Al showed a maximum brightness of 1389 cd m(-2) at 12 V and a maximum efficiency of 3.29 cd A(-1).

Organic semiconductors show efficient electroluminescence which has led to their commercialization in light-emitting diodes (LEDs), however, they have been marred by the thorniest problem of solid-state quenching. Here, we report the synthesis and characterization of two fluorene-based blue amphiphile emitters containing triphenylamine or anthracene side groups and demonstrate formation of their hybrid meso-structured nanocomposites by sol-gel co-assembly with tetraethyl orthosilicate; and study the molecular interactions within the mesophases formed. The chromophore amphiphiles designed act as photonic active materials as well as structure-directing agents. The new blue luminescent fluorene-based amphiphile/silica co-assembled nanocomposite films have been successfully prepared with enhanced emission. Different kinds of light emitting devices based on these nanocomposites show efficiencies which are improved by several times compared with the corresponding pristine chromophore amphiphiles.

We report the fabrication and electroluminescence (EL) characterization of a white-emitting hybrid organic/inorganic light emitting device (LED) by integrating core-shell CdSe/ZnS quantum dots (QDs) acting as a yellow emitter and polyfluorenes as the blue emitter in a multilayered structure. The hybrid white-emitting device was fabricated by spin-coating QDs in varied concentrations onto the layer of polyfluorenes with different functional groups (i.e., sulfur-containing PF1 and PFO). Depending on the QDs concentrations and the design of the hybrid LED, our device is able to exhibit either electroluminescence from QDs or a combination of both PF and QD. The EL spectra at different driving voltages, I-V characteristics, and EL chromaticity of the LEDs based on PF1/QD and PFO/QD LEDs have been measured, investigated, and compared, respectively.