We also demonstrate the synthesis of a crystalline YVO4:YbVO4 layered material by ALD to verify the possibility of creating artificial coreshell type. The PL intensity of Eu 3+ increases with increasing the annealing temperature and the values of W. In the present contribution we assess the efficiency of the UV to NIR conversion in the produced films and determine the optimal pulse parameters with respect to NIR emission intensity. The Eu 3+ shows a strong PL luminescence (dominated by 5D 0 - 7F 2 red emission at 618 nm) under the excitation of 320 nm UV light. The luminescence intensity and lifetime of those samples were less than those of their counterpart core samples. The silanol group (SiOH) is present in silica coated samples (heated up to 500 C) and acts as luminescence quencher. Highly luminescent YVO4Eu3+ nanocrystals (NCs) coating on wirelike Y(OH)3Eu3+ and Y2O3Eu3+ microcrystals were synthesized by a chemical corrosion method, that is, first preparation of Y(OH)3Eu3+ wirelike microcrystals by a hydrothermal method, and subsequently chemical corrosion with NaVO4 solutions through a second hydrothermal treatment. The thickness of the YVO 4:Eu 3+ shells on the SiO 2 cores could be easily tailored by changing the mass ratio of shell to core ( W = /) ( 50 nm for W = 30%). Successful coating of the silica on the YVO 4:Ln 3+ core could be observed by transmission electron microscopy. Meanwhile, the as-prepared coreshell structured nanocomposite (YVO4:EuMIPs), which was composed of lanthanide doped YVO4:Eu as fluorescent signal and. on SiO2 spheres was a good choice to yield core-shell structured nano-phosphors. 500 nm and an average thickness of 50 nm), are not agglomerated, and have a smooth surface. For example, the YVO4 :Ln3 sol precursor could be coated onto a planar. Complex oxide YVO4 multi-shell hollow spheres with uniform morphologies and controllable shell numbers are successfully prepared by using a newly developed and general composite yttrium-carbonaceous sphere templated approach. The obtained core-shell phosphors have a near perfect spherical shape with narrow size distribution (average size ca. The XRD results demonstrate that the Y 0.95Eu 0.05VO 4 particles crystallization on the surface of SiO 2 annealing at 800 ☌ is perfectly and the crystallinity increases with raising the annealing temperature. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and photoluminescence (PL) spectra were used to characterize the resulting SiO 0.95Eu 0.05VO 4 core-shell phosphors. In this work, a novel core-shell and inorganicorganic hybridization strategy has been employed to fabricate Eu3+-doped YVO4 nanoparticles to broaden their photoluminescence excitation spectral bandwidth to the range of 230415 nm, covering the entire ultraviolet spectrum of solar light and enabling their potential applications in silicon. We report an efficient process for preparing monodisperse SiO 0.95Eu 0.05VO 4 core-shell phosphors using a simple citrate sol-gel method and without the use of surface-coupling silane agents or large stabilizers.
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