Spectroscopic studies of silica-incorporated lanthanum ?2-diketonate complexes for application in optoelectronic devices

摘要： In the present research work, silica-incorporated complexes of lanthanum β-diketonate were synthesized. Structural characterization of the prepared complexes was made on the basis of FTIR and FESEM studies. Shifting of peaks in the FTIR spectra are discussed in relation with the complexation, also incorporation of silica in complexes was confirmed by the FTIR spectra. FESEM and EDX studies were performed to know the surface morphology as well as elemental composition of the prepared complexes. The optical properties such as diffuse reflectance and photoluminescence were studied to get the idea about the possible transitions among the energy levels of the complexes as well as to know the emission peaks. The assignment of luminescence band is determined from excited state lifetime. The variation in luminescence intensity with time was measured by recording decay curves at fixed emission wavelength. The life time for all the three complexes was measured in micro-second (μs) order. Color coordinates of the complexes lie in the blue region. Thermal stability of the complexes was checked by measuring the loss in weight as a function of temperature.