Investigation of the Photoluminescence and Nonlinear Optical Properties of Ce₂O₃-TiO₂ Nanocomposites

This paper reports the photoluminescence and nonlinear optical (NLO) properties of Ce₂O₃-TiO₂ nanocomposites synthesized via sol-gel process with different concentrations of cerium. The physical characterization studies by means of XRD indicated for the successful incorporation of Ce into the lattice of TiO₂, while the UV-visible spectra for an absorption edge shift of TiO₂ to the higher wavelength side following the Ce addition, and FESEM analysis for the morphology and particles sizes of the synthesized materials. On testing of the photoluminescence properties recorded through time-resolved fluorescence (TCSPC) technique, a decrease in the intensity of TiO₂ with that of increased Ce concentration was observed and is due to an escalation in the number of oxygen vacancies. Further, the observation NLO properties for Ce₂O₃-TiO₂ was done by a Z-scan technique of 5ns continuous wave (cw) laser at 532 nm, where the involvement of active mechanisms in the nonlinear refraction and nonlinear absorption are due to the saturable absorption (SA) and nonlinear thermal effects.