Portrayal of structural, thermal and optical properties of pH sensitive Eu(TTA)3bipy hybrid organic complex for OLEDs

Abstract

Europium activated hybrid organic tris(thenoyltrifluoracetonate)(2,2′-bipyridine)europium(III), Eu(TTA)3bipy complexes were synthesized at different pH values, ranging between 8.0 and 6.0 by solution technique. Among the synthesized, the complex with pH 7.5 showed maximum peak intensity centered at 614nm with a narrow full width at half maxima (FWHM) under excitation wavelength of ∼381nm. The chromaticity co-ordinates of these complexes were found to be in the range of (0.602, 0.326)–(0.669, 0.335). The electronic absorption spectra of Eu complexes with a variation in the solvent from basic to acidic illustrates the evidence of staggering difference in optical absorptions with a noticeable bathochromic shift. X-ray diffractogram of the complex reveals its crystalline nature and scanning electron microscopy (SEM) illustrates that the complex have crystalline grains and exhibits globular surface morphology. FTIR spectra confirms the structure formation and molecular bonding of the synthesized complex, while TGA/DTA curve reveals its superior thermal stability to about 221.24°C, proving it’s potential as red emissive materials for OLEDs.