Phosphor Ca₂La_6.8Eu_1.2(SiO₄)₆O_2−δ is obtained via coprecipitation and the nitrate-citrate pyrolysis method. The structure and phase composition of the synthesized apatite silicates are studied using XRD. The luminescence spectra of the sample are registered before and after pressing at pressures above 5 GPa. The magnetic properties are analyzed by means of ESR spectroscopy and vibration magnetometry. The concentrations of Eu²⁺ ions and constants (λ) of optical splitting between ⁷F_J levels in the initial sample, and in the sample after hot pressing, are calculated.

In this work, a new phosphors Ca₂La_6.8Eu_1.2Ge_5.6W_0.4O_26.4-δ and CaLa_7.875Eu_1.125Ge_5.6W_0.4O_26.9-δ for the n-LED as well as Sr₂La_8-2xEr_xYb_xGe₆O₂₆, x=0.01; 0.05; 0.075; 0.1 0.15 solid solutions, that are for the conversion of the near infrared emission in the visible light, are described. Synthesis procedure, by the sol-gel method, of the studied compounds set out in detail. Photoluminescence spectra of the Ca₂La_6.8Eu_1.2Ge_5.6W_0.4O_26.4-δ and CaLa_7.875Eu_1.125Ge_5.6W_0.4O_26.9-δ compounds, and upconversion spectra of the Sr₂La_8-2xEr_xYb_xGe₆O₂₆ luminophors are measured. Present of the Eu³⁺ and Eu²⁺ ions in the Ca₂La_6.8Eu_1.2Ge_5.6W_0.4O_26.4-δ and CaLa_7.875Eu_1.125Ge_5.6W_0.4O_26.9-δ phosphors has been evidenced. Color coordinates of the Ca₂La_6.8Eu_1.2Ge_5.6W_0.4O_26.4-δ and CaLa_7.875Eu_1.125Ge_5.6W_0.4O_26.9-δ compounds were calculated.

The effect of the substitution of [GeO₄]⁴⁻ groups by [PO₄]³ in the anionic sublattice of apatite-structure inorganic luminophores activated with Eu³⁺ ions on their luminescence and crystal chemical properties has been studied. A number of solid solutions with a general formula of Ca₂La_7.2Eu_0.8(GeO₄)_6−x(PO₄)_xO₂ (x = 0.18, 0.3, 0.48, 0.6, 0.78) have been synthesized. Using the luminescence spectroscopy and electron paramagnetic resonance (EPR) methods, it has been shown that Eu³⁺ in the structure of the synthesized crystal phosphors undergoes reduction to Eu²⁺. For compounds with x = 0.18 and 0.48, the effect of the composition on the strength of the crystal field acting on Eu³⁺ ions has been shown. The phonon sublattice has been studied by the IR and Raman spectroscopy methods. A decrease in the integrated luminescence intensity for the selected type of substitution has been shown. The data obtained can be used to design effective luminophores for some fields of technology, such as the design of scitillation detectors, television systems, and photodiodes.

This study investigates the synthesis and characterization of boron-modified nanotubular titania (NTO) arrays fabricated via a single-step anodizing process with varying concentrations of boric acid (BA). Following anodization, a reductive heat treatment was applied to facilitate the crystallization of the anatase phase in the boron-modified NTO. The effect of the BA concentration on the structural, morphological, and photoelectrochemical (PEC) properties of the NTOs was systematically explored through scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), luminescence, and UV-Vis spectrometry. The introduction of boron during anodization facilitated the formation of sub-bandgap states, thereby enhancing the light absorption and electron mobility. This study revealed the optimal BA concentration that yielded a 3.3-fold enhancement of the PEC performance, attributed to a reduction in the bandgap energy. Notably, the highest incident photon-to-current conversion efficiency (IPCE) was observed for NTO samples anodized at a 0.10 M BA concentration. These findings underscore the promise of boron-modified NTOs for advanced photocatalytic applications, particularly in solar-driven water-splitting processes.

Polycrystalline phosphors with a Sr2Y8-x-yYbyTmxSi6O26 (x=0.005-0.5, y=0.2,0.3) total formula were synthesized. Nanoluminophor has been obtained from the Sr2Y7.695Yb0.3Tm0.005Si6O26 microcrystalline sample by the vacuum electron been evaporation, in the amorphous state, with the ~10.6 nm particle size. It is found, raman spectra undergoing modification by the transition from bulk- to nanosize state. Photoluminescene spectra micro- and nanophosphors are studied. Intensity of the blue emission, by the UV ligth excitation, grows in the x=0.005-0.02 region, with the x increasing. Upconversion photoluminescence (UPCL) spectra of the bulk phosphors and nanosample based on the Sr2Y7.695Yb0.3Tm0.005Si6O26 were measurd. At the pumping power around 70.8 mW, by the laser source with the λ=980 nm, thereshold population of the 3F3 level of Tm3+ ions exist. At a power higher 70.8 mW, a sharp increase of the luminescence intensityof the bulk- and nanophosphor occurs. For the 3H4->3H6 transition thereshold pumping power absent. This indicates that, pumping, during Yb->Tm energy transer, is a single photon process.

The aim of this research work is to study the effect of substitution in the anionic lattice of inorganic phosphors activated by Eu3+ ions with an apatite-type structure of [GeO4]4– by [PO4]3 groups on their luminescent and crystal chemical properties. A number of solid solutions with the general formula Ca2La7.2Eu0.8(GeO4)6–x(PO4)xO2+x/2–δ (1) have been synthesized. The reduction of Eu3+ to Eu2+ in the structure of synthesized crystal phosphors has been shown by methods of luminescent spectroscopy and electron paramagnetic resonance (EPR). For compounds with x = 0.18 and 0.48, the effect of the composition on the strength of the crystal field acting on Eu3+ ions is shown. The phonon sublattice was studied using IR and Raman spectroscopy methods. A decrease in the integral luminescence intensity is shown for the selected type of illumination. The obtained data can be used to create effective phosphors for such technological fields as the creation of scitillation detectors, television devices and photodiodes.