In situ sol-gel composition of inorganic/organic polymeric hybrid precursors to synthesize red-luminescent CaTiO3:Pr3+ and CaTi0.5Zr0.5O3:Pr3+ phosphors

In this paper, rare earth coordination polymers with aromatic carboxylic acids were used as the precursors of luminescent species, composed with polyethylene glycol (PEG) to achieve inorganic/organic hybrid polymeric dispersing media. The resulting multicomponent hybrid precursors were assembled by an in situ sol-gel process of tert-n-butyl titanate (Ti(OC4H9)4) and further thermal decomposed to obtain two series of rare earth oxysalts phosphors: CaTiO3:Pr3+ and Ca(Ti0.5Zr0.5)O3:Pr3+. Both XRD and SEM indicated the particle sizes of them were in the range of around 1 μm. The excitation spectra presented a broad spectral band in the visible blue-violet region with the maximum excitation peak at 445 nm, while no apparent absorption appeared in ultraviolet region. The corresponding emission spectra showed a wide emission range with a maximum peak at 619 nm, which was ascribed to be the characteristic transition of Pr3+ (1D2 → 3H4), which can be expected for visible light conversion materials.