Synthesis and characterization of pure and Li+ activated Alq3 complexes for green and blue organic light emitting diodes and display devices

Pure and Li+-doped Alq(3) complexes were synthesized by simple precipitation method at room temperature, maintaining the stoichiometric ratio. These complexes were characterized by X-ray diffraction, ultraviolet-visible absorption and Fourier transform infrared and photoluminescence (PL) spectra. X-ray diffraction analysis reveals the crystalline nature of the synthesized complexes, while Fourier transform infrared spectroscopy confirm the molecular structure, the completion of quinoline ring formation and presence of quinoline structure in the metal complex. Ultraviolet-visible and PL spectra revealed that Li+ activated Alq(3) complexes exhibit the highest intensity in comparison to pure Alq(3) phosphor. Thus, Li+ enhances PL emission intensity when doped into Alq(3) phosphor. The excitation spectra lie in the range of 383-456 nm. All the synthesized complexes other than Liq give green emission, while Liq gives blue emission with enhanced intensity. Thus, he synthesized phosphors are the best suitable candidates for green- and blue-emitting organic light emitting diode, PL liquid-crystal display and solid-state lighting applications. Copyright (C) 2013 John Wiley & Sons, Ltd.