In this paper, a series of Sr0.96Al2Si2O8 phosphors doped with 0.02Eu2+ and 0.02Re3+ (where Re = Tm, Dy, Er, Nd, Sm, La, Ho) were synthesized using the high-temperature solid-phase method at 1350 °C for 4 hours. The samples underwent characterization for structural and phase analysis using XRD-6000. Fluorescence and photostimulated properties were evaluated with F-4600. The pyroluminescence curve indicates a trap depth of 0.6-0.8 eV for Sr0.96Al2Si2O8: 0.02Eu2+, 0.02Re3+ (where Re = Dy, Er, Sm, La, Ho), making it suitable for prolonged afterglow luminescence. In comparison with deep trap material Sr0.96Al2Si2O8: 0.02Eu2+, 0.02Nd3+, the generated traps approach or exceed 1 eV, suggesting its potential for use as a light excitation and optical storage material. Additionally, the correlation between sample TL and PSL was examined, confirming that the augmentation of initial photostimulated luminescence intensity is closely associated with the generation of new traps. Furthermore, considering the effect of different trivalent lanthanide rare earth ion doping on trap depth from a trap regulation perspective offers a potential avenue for elucidating the nuanced processes underlying photostimulated luminescence.
In this work, we have prepared the RE3+ (re = Sm, Dy): MgLa2V2O9 phosphors of different mol% by solid-state reaction approach. The obtained powder phosphors of RE3+ (re = Sm, Dy): MgLa2V2O9 were analyzed by SEM, XRD, FTIR, EDAX, PL spectroscopy, and CIE chromaticity diagram of the color of different mol%. The XRD pattern of the powder phosphors exhibits the phosphor's crystalline nature. The obtained size of prepared phosphors is around the size of 500 nm was observed by analysis of SEM. The element's existence in the phosphors was obtained by analysis of EDAX. Functional groups were identified by FTIR analysis. From the PL analysis SE3+ (re = Sm, Dy): MgLa2V2O9 phosphors show intense orange-red emission at 599 nm, that is attributed to the (4)G(5/2 )-> H-6(7/2) transition having an excitation lambda(exci)=404nm (6H(5/2 )-> F-4(7/2)). It exhibits yellow emission for Dy3+ (re = Sm, Dy): MgLa2V2O9 at 574 nm having a transition of F-4(9/2 )-> (6)H(13/2 )having an excitation wavelength lambda exci.= (H-6(15/2)-> I-4(15/2)). The CIE diagram shows the orange and yellow emission for Sm3+: MgLa(2)V(2)O(9 )and Dy3+:MgLa2V2O9 correspondingly. The CIE coordinates shows that the great purity of color of the phosphors powder.
Motivated by the recently discovered superconductivity in Sr-doped nickelate oxides NdNiO2, we predict a material BiNiO2 that provides an opportunity to study the intertwined ferroelectricity, metallicity, and magnetism in a crystal with very simple atomic structures.There is a ferroelectric structural transition from the nonpolar phase with the P4/mmm space group to the polar phase with the P4mm space group, which is driven by the lone pair on Bi.Calculations based on the Heyd-Scuseria-Ernzerhof hybrid density functional reveal that both the nonmagnetic and ferromagnetic states are metallic for nonpolar and polar phases, while the lowest energy ground-state for polar BiNiO2 is a Hubbard Mott insulator with the G-type antiferromagnetic spin configurations.As a ferroelectric material with an electric polarization of 0.49 C/m 2 , it may be possible to control the magnetic order in BiNiO2 by an applied electric field.The replacement of Nd by Bi serves as a connecting link between a high-temperature superconductor and a Mott multiferroic.Our work supports a route towards strongly correlated ferroelectrics.
In this work, we have prepared the RE3+(Sm, Dy): MgLa2V2O9 phosphors of different mol% by solid-state reaction approach. The obtained powder phosphors of RE3+(Sm, Dy): MgLa2V2O9 were analyzed by SEM, XRD, FTIR, EDAX, PL spectroscopy, and CIE chromaticity diagram of the color of different mol%. The XRD pattern of the powder phosphors exhibits the phosphor's crystalline nature. The obtained size of prepared phosphors is around the size of 500 nm was observed by analysis of SEM. The element's existence in the phosphors was obtained by analysis of EDAX. Functional groups were identified by FTIR analysis. From the PL analysis Sm3+: MgLa2V2O9 phosphors show intense orange-red emission at 599 nm, that is attributed to the 4G5/2→6H7/2 transition having an excitation λexci=404nm (6H5/2→4F7/2). It exhibits yellow emission for Dy3+: MgLa2V2O9at 574 nm having a transition of 4F9/2→6H13/2having an excitation wavelength λexci.= (6H15/2→4I15/2). The CIE diagram shows the orange and yellow emission for Sm3+: MgLa2V2O9 and Dy3+:MgLa2V2O9correspondingly. The CIE coordinates shows that the great purity of color of the phosphors powder.
In the framework of the density functional theory electronic band structure and density of states of LaxBa1-xMnO3 solid solutions containing different concentrations of La and Ba atoms, were studied using different exchange correlation functionals. Our calculation show that the band gap, which characterizes the properties of semiconductors, varies depending on the concentration of La and Ba atoms in the compounds. Using such a dependence, it is possible to make changes in physical properties depending on the concentration of cations.
