In Situ Preparation and Luminescent Properties of CeF₃ and CeF₃:Tb³⁺ Nanoparticles and Transparent CeF₃:Tb³⁺/PMMA Nanocomposites in the Visible Spectral Range

CeF 3 and CeF 3:Tb 3+ nanoparticles were prepared by reverse microemulsion with a functional monomer, methyl methacrylate (MMA), as the oil phase, and CeF 3:Tb 3+ /poly (methyl methacrylate) (PMMA) nanocomposites were obtained via polymerization of the MMA monomer. The nanoparticles and nanocomposites have been well characterized by X−ray diffraction (XRD), scanning electron microscopy (SEM), low- and high-resolution transmission electron microscope (TEM), selected-area electron diffraction (SAED), thermogravimetric analysis (TGA), UV/vis transmission spectra, photoluminescence excitation, and emission spectra and luminescence decays. The well-crystallized CeF 3 and CeF 3:Tb 3+ nanoparticles are spherical with a mean diameter of 15 nm. They show the characteristic emission of Ce 3+ 5d-4f (313 nm, 2 D- 2 F 5/2; 323 nm, 2 D- 2 F 7/2 ) and Tb 3+ 5 D 4 - 7 F J ( J = 6−3, with 5 D 4 - 7 F 5 green emission at 541 nm as the strongest one) transitions, respectively. The energy transfer from Ce 3+ to Tb 3+ was investigated in CeF 3:Tb 3+ nanoparticles in detail. The obtained solid CeF 3:Tb 3+ /PMMA nanocomposites are highly transparent (in the visible spectral range) and exhibit strong green photoluminescence upon UV excitation, due to the integration of luminescent CeF 3:Tb 3+ nanoparticles. The luminescent lifetime of Tb 3+ is determined to be 4.1 ms in the nanocomposite.