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Conducting metallopolymers have been investigated for a variety of applications due to their ability to take advantage of both the mechanical processability of the polymer material, as well as the optical and electronic properties of the metal. Our project goal is to design, synthesize and characterize novel iridium(III)-containing conducting metallopolymers for use as the active layer in polymer light-emitting diodes. We have utilized thiophene functionalized ligands that can be readily electropolymerized into conducting polymer thin films and can be easily incorporated into a device structure. Iridium(III) was chosen as the metal center due to its promising photophysical properties, as similar complexes have demonstrated high luminescent quantum yields and short phosphorescent lifetimes. The coordination environment around the metal can be altered synthetically to tune the emission wavelength across the visible spectrum. The synthetic control over the polymer backbone, as well as the iridium(III) ligand environment, allowed us to independently vary each component, which has provided a variety of materials. The materials are characterized through 1H and 13C NMR, mass spectrometry, elemental analysis, electrochemistry, X-Ray diffraction and X-Ray Photoelectron Spectroscopy. The photophysical properties of the materials are studied through UVvii Visible absorption spectroscopy, UV-Vis-NIR spectroelectrochemistry and steadystate/ time-resolved emission spectroscopy.

The performance of polymer light emitting diode (PLED) strongly depends on materials, fabrication and the structure of the device. Polymer light-emitting diodes typically consists of emitting layer(s) sandwiched between a cathode and an anode. In our study indium tin oxide (ITO) is used as anode, the polymer blend as emitting layer and metals such as aluminum, silver as cathodes. Investigation in this area is focused to fully understand and develop the method of fabrication of PLEDs using the available resources and to understand the effect of variation of blend ratios of polyfluorene polymers (TFB: 9, 9'-dioctylfluorene-co-N-(4-butylphenyl) diphenylamine and F8BT: poly (9, 9'dioctylfluorene- co-benzothiadiazole)), different cathodes, addition of buffer layer (calcium acetylacetonate [Ca (acac)z]) on the built devices.