Laser and electromagnetic loss properties of Perovskite SmNi<Subscript>x</Subscript>Fe<Subscript>1−x</Subscript>O<Subscript>3</Subscript>

SmNi_xFe_1?xO₃ (0?≤?x?≤?0.5) with perovskite-type structure has been successfully prepared by conventional solid-state reaction as a microwave and laser multi-functional material. The optimized synthesis temperature and the effects of Ni doping on the reflectivity, electromagnetic loss properties were investigated in details. XRD results shown that synthesis temperature did not change the perovskite structure of SmFeO₃. The reflectivity at 1.06 μm was about 0.33% at 1200–1300?°C. Doping Ni did not cause the change of perovskite structure. The incorporation of Ni in SmFeO₃ contributed to the decrease of reflectivity at a wider wavelength, SmNi_0.3Fe_0.7O₃ possessed the lowest reflectivity at 1.06 μm. Moreover, electromagnetic property was very sensitive to Ni content. The real and imaginary parts of complex permeability were enhanced remarkably at a certain frequency. The changes in magnetic performance provided possibility of choosing specific frequency of magnetic loss. The difference in electric and magnetic losses caused by Ni concentration could result in microwave absorption at different frequency. In a word, SmNi_xFe_1?xO₃ could be a promising candidate for a multi-functional material with compatible camouflage capability for radar and laser waveband.     

Preparation and luminescence properties of Y<Subscript>3−y</Subscript>Al<Subscript>5−x</Subscript>Ga<Subscript>x</Subscript>O<Subscript>12</Subscript>:Ce<Superscript>3+</Superscript><Subscript>y</Subscript> phosphors

Y_3?yAl_5?xGa_xO₁₂:Ce³⁺_y phosphors were prepared by high temperature solid state reaction method. The crystal structures, the influence of Ga³⁺ concentration on the photoluminescence (PL), cathodoluminescence, thermal stability and morphology of the phosphors were studied in detail. The results indicated that diffraction angle of the samples decreased gradually with the increase of Ga³⁺ ions content in XRD pattern. The emission peak of the spectra show a progressive blue-shift, the intensity increased first and then decreased and the optimal Ga³⁺ concentration in Y_2.94Al_5?xGa_xO₁₂:Ce³⁺_0.06 phosphors is x?=?0.75. The critical concentration of Ce³⁺ in YAGG:Ce³⁺ phosphors is affected with the ratio of Ga³⁺ to Al³⁺ and the Y_2.9Al_4.25Ga_0.75O₁₂:Ce³⁺_0.1 phosphor showed the best performance on PL. However, the optimum concentration of Y_3?yAl_5?xGa_xO₁₂:Ce³⁺_y phosphors is x?=?1.5 and y?=?0.04 when they were excited by cathode ray.     

Microscopic and macroscopic magnetic properties of MgAl<Subscript>x</Subscript>Cr<Subscript>x</Subscript>Fe<Subscript>2 − 2x</Subscript>O<Subscript>4</Subscript> spinel ferrite system

In order to study the effect of co-substitution of Al^{3 +} and Cr^{3 +} for Fe³⁺ in MgFe₂O₄ on its structural and magnetic properties, the spinel system MgAl _x Cr_xFe_{2 ? 2x}O₄ (x = 0.0–0.8) has been characterized by X-ray diffraction, high field magnetization, low field a.c. susceptibility and ⁵⁷Fe Mössbauer spectroscopy measurements. Contrary to the earlier reports, about 50% of Al^{3 +} is found to occupy the tetrahedral sites. The system exhibits canted spin structure and a central paramagnetic doublet was found superimposed on the magnetic sextet in the Mössbauer spectra (0.5 > x > 0.2). Thermal variation of a.c. susceptibility exhibits normal ferrimagnetic behaviour.     

Effects on dielectric and magnetic properties of Cr-doped Bi<Subscript>0.9</Subscript>Ba<Subscript>0.1</Subscript>Fe<Subscript>1−x</Subscript>Cr<Subscript>x</Subscript>O<Subscript>3</Subscript> ceramic

In this paper, Cr-doped Bi_0.9Ba_0.1Fe_1?xCr_xO₃ (x = 0.00, 0.05, 0.10, 0.15, 0.20) ceramic materials were prepared by traditional state solid synthesized method, and the effects of Cr³⁺ ion on magnetic and dielectric properties were investigated. All samples showed BiFeO₃ phase formation were successful synthesized. The SEM images showed the shape of samples changed from regular to irregular shape. With increasing of Cr²⁺ ions, Saturation magnetization (M _s) increased from 5.24 to 8.6 emu/g, and then decreased to 7.31 emu/g, and coercivity (H _c) increased from 110.66 to 256.49 Oe. All the samples showed high dielectric constants at low frequency and the values of dielectric constants decreased slightly with frequency increasing. Delectric loss (tanδ) values kept a steady in a wide range frequency of 10–600 MHz. They ranged in tanδ from 0.01 to 0.07, which was a low dielectric loss in Bi_0.9Ba_0.1Fe_1?xCr_xO₃ ceramics.     

Ba<Subscript>1−x</Subscript>La<Subscript>x</Subscript>Fe<Subscript>12</Subscript>O<Subscript>19</Subscript> (x = 0.0, 0.2, 0.4, 0.6) hollow microspheres: material parameters,magnetic and microwave absorbing properties

Ba_1?xLa_xFe₁₂O₁₉ (x = 0.0, 0.2, 0.4, 0.6) hollow ceramic microspheres (HCMs) have been prepared by combining self-reactive quenching method with heat treatment. Their material parameters, magnetic and microwave absorbing properties were investigated. It was observed that after doping of lanthanum, the material parameters showed a little change except hexagonal crystal disappearing. And the magnetic properties of HCMs were decided by lanthanum content and material parameters. With the lathanum increases from 0.0 to 0.6, the saturation magnetization (Ms) values initially increased, and then decreased sharply to a minimum value, and increased again, moreover, the coercive force (Hc) values were reduced first, and then increased, and decrease to a minimum value. Absorbing properties tests indicate that after La³⁺-doped, at 2 mm thickness, the effective absorbing band (<?10 dB) was reduced to 4.7, 5 and 4.4 GHz, respectively, the minimum reflectance would decrease in low substituted level (x ≤ 0.4) and increase in high level (x = 0.6), and the frequency shifts to low frequency with the increasing of doping content. In 1.5–3 mm range, with the increasing of thickness, the absorption peak of Ba_1?xLa_xFe₁₂O₁₉ (x = 0.2, 0.4, 0.6) HCMs shifts to low frequency and the absorption intensity increases, the effective absorbing band can up to 10, 8.1 and 8 GHz, respectively.     

Rational synthesis and tailored optical and magnetic characteristics of Fe<Subscript>3</Subscript>O<Subscript>4</Subscript>–Au composite nanoparticles

To minimize saturation magnetization (Ms) degradation and simultaneously maintain the optical and magnetic responsiveness characteristics of Fe₃O₄/Au nanocomposites, we successfully prepared Fe₃O₄–Au seeds composite nanoparticles (NPs) by a novel seed deposition process. The effects of gold seeds coating amounts and the concentration of Fe₃O₄ NPs on the morphologies of final products are extensively characterized. The results of energy-dispersive spectrometry mapping show that the gold seeds are uniformly adhered onto the Fe₃O₄ NPs surfaces in precisely controlled amount. Importantly, with the electronic redistribution between Fe₃O₄ and Au NPs interfaces, the obvious position shifting of Fe 2p and Au 4f electronic binding energy peaks is observed. Upon increasing surface coatings of gold seeds, the electron deficiency on the gold NPs leads to the redshift of the absorption peak. Though Ms declines slightly due to the diamagnetic contribution from decorated gold seeds, the developed Fe₃O₄–Au seeds composite NPs possess the robust magnetic responsiveness and they are amenable to be separated and recycled by the external magnet, which facilitates great potential applications in biological, medical and photocatalytic fields.     

Preparation,characterization and dielectric properties of Ba<Subscript>3−x</Subscript>Sr<Subscript>x</Subscript>LiM<Subscript>3</Subscript>Ti<Subscript>5</Subscript>O<Subscript>21</Subscript>[M=Nb and Ta,x = 0 to 3] ceramics

The ceramic compositions Ba_3−xSr_xLiM₃Ti₅O₂₁[M=Nb and Ta, x = 0 to 3] were prepared through conventional solid state ceramic route. A detailed study has been carried out to correlate the structure of Ba_3−xSr_xLiM₃Ti₅O₂₁[M=Nb and Ta, x = 0 to 3] with respect to their dielectric properties. The structure and microstructure of ceramic samples were studied using powder X-ray diffractometer and Scanning Electron Microscopic techniques. The dielectric properties of the sintered ceramic compacts have been studied. The Ba-rich compositions were identified as promising candidates for high frequency applications whereas the Sr-rich compositions were excellent ionic conductors and can be commercially exploited for applications in solid-state batteries.     

Structural,magnetic and magnetocaloric investigation of La<Subscript>0.67</Subscript>Ba<Subscript>0.33</Subscript>Mn<Subscript>1−x</Subscript>Ni<Subscript>x</Subscript>O<Subscript>3</Subscript> (x = 0, 0.025 and 0.075) manganite

In this paper, we report the structural, magnetic and magnetocaloric properties of Ni-doped La_0.67Ba_0.33Mn_1?xNi_xO₃ (x?=?0, 0.025 and 0.075) manganites. Our compounds were synthesized using the sol–gel method. The structural analysis using Rietveld refinement shows that Ni-doped LaBaMnO₃ system crystallizes in the rhombohedral symmetry with \({\text{R}}\bar {3}{\text{c}}\) space group. Magnetization measurements versus temperature in a magnetic applied field of 0.05 T reveal that all the compositions exhibit a transition from a ferromagnetic to paramagnetic phase with increasing temperature. A systematic decrease in the transition temperature is clearly observed upon Ni doping and a near room temperature T_C (302 K) is achieved with x?=?0.075 composition. The maximum magnetic entropy change \(\left( { - ~\Delta {\text{S}}_{{\text{M}}}^{{\hbox{max} }}} \right)\) in a magnetic field change of 5 T is found to be 2.12, 2.78 and 1.78 J/kg K for x?=?0, 0.025 and 0.075, respectively. At this value of magnetic field, large relative cooling power values are obtained in our samples, especially for x?=?0.075 (271 J/kg) making it a promising candidate for magnetic refrigeration near room temperature.     

Structural Stability of SrCo<Subscript>1 − <Emphasis Type="Italic">x</Emphasis></Subscript>Fe<Subscript>x</Subscript>O<Subscript>3 − δ</Subscript> Solid Solutions

SrCo_{1 − x} Fe_xO_{3 − δ} solid solutions with 0.3 ≤ x ≤ 0.9 are shown to have the cubic perovskite structure. The unit-cell parameter and volume of the solid solutions are nonmonotonic functions of Fe content, with a minimum at x = 0.4. Dilatometric data are used to determine the thermal expansion coefficients of the solid solutions. At low oxygen partial pressures ( ≤ 40 Pa), the high-temperature, disordered perovskite phase exists between 850 and 1000°C, which is the optimal temperature range for the effective use of SrCo_{1 − x} F_xO_{3 − δ} ceramics as oxygen membranes in oxygen partial pressure gradients of 10⁴–10⁵/10–100 Pa.__________Translated from Neorganicheskie Materialy, Vol. 41, No. 8, 2005, pp. 998–1004.Original Russian Text Copyright © 2005 by Kokhanovskii, Zonov, Ol’shevskaya, Pan’kov.     

Effect of annealing on exchange bias in Mg<Subscript>0.2</Subscript>Fe<Subscript>x</Subscript>Cr<Subscript>1.8−x</Subscript>O<Subscript>3</Subscript> nano oxides

Magnesium-iron chromium oxides (Mg_0.2Cr_1.8?x Fe _x O₃ with x varying from 0.3 to 0.9) produced by hydrothermal process in a stirred pressure reactor from pure metal chlorides have been annealed at 700 °C. Single phase corundum structure and nanophase structure of the as-synthesized samples were confirmed by X-ray diffraction (XRD). Instead of the correlation between H _EB and D _XRD observed at T _A = 600 °C, we find significant changes. The H _EB increases with decreasing particle size reaches a maximum at ~43 nm (x = 0.5) then decreases.     

Microstructure and properties of the Ba<Subscript>0.75−x</Subscript>Ca<Subscript>x</Subscript>La<Subscript>0.25</Subscript>Fe<Subscript>11.6</Subscript>Co<Subscript>0.25</Subscript>Ti<Subscript>0.15</Subscript>O<Subscript>19</Subscript> hexaferrites

In the case of Ti⁴⁺ remain unchanged, the Ca²⁺ substituted Ba_0.75?xCa_xLa_0.25Fe_11.6Co_0.25Ti_0.15O₁₉ (0?≤?x?≤?0.05) were prepared by conventional solid-state reaction method at temperature of 1280 °C. A ball-to-power weight ratio of 10:1. Their crystal structure and magnetic properties were mainly investigated. The results show that the single magnetoplumbite phase structure transformed into the multiphase structure. Meanwhile, the small amount of α-Fe₂O₃ phase existed in M-type phase. The micrographs were observed by a field emission scanning electron microscopy (SEM). Vibrating sample magnetometer (VSM) was used to analyze the magnetic properties. The saturation magnetization (M _s ) first increases then decreases when x from 0 to 0.03. But, when x from 0.03 to 0.05, the saturation magnetization (M _s ) first increases then decreases too. The maximum value is at x?=?0.04 (M _s ?=?70.73 emu/g). The value of coercivity (H _c ) first increases then decreases when x from 0 to 0.04. But, the value increased when x from 0.04 to 0.05. The maximum value is at x?=?0.02 (H _c ?=?1691 Oe).     

Structural and optical absorption studies of cobalt substituted strontium ferrites,SrCo<Subscript>x</Subscript>Fe<Subscript>12−x</Subscript>O<Subscript>19</Subscript> (x = 0.1, 0.2 and 0.3)

Cobalt substituted strontium ferrites SrCo_xFe_12?xO₁₉ (x = 0.1, 0.2 and 0.3) were synthesized via sol–gel method and the dried gel obtained was annealed at 800 °C. The powder X-ray diffraction studies helped in the determination of the crystallite size that measured ≈ 12–14 nm. The optical properties of the powdered nanoparticles were determined by means of the UV–Vis absorption spectra of their dispersed solutions in liquid media. Despite these measurements, it was difficult to determine their band gap (E_g) precisely. However, the Kubelka–Munk treatment on the diffuse reflectance spectra of the powdered nanoparticles was used in order to extract their E_g unambiguously. The Co substituted strontium hexaferrites are used for optical studies. The energy band gap for all the ferrite compositions was found to be ≈ 1.46–1.78 eV. The study made on the dielectric behaviour of the substituted SrFe₁₂O₁₉ is also discussed in this paper.     

Micro-structural,dielectric, ferroelectric and piezoelectric properties of mechanically processed (Pb<Subscript>1−x</Subscript>La<Subscript>x</Subscript>)(Zr<Subscript>0.60</Subscript>Ti<Subscript>0.40</Subscript>)O<Subscript>3</Subscript> ceramics

In this work, (Pb_1?xLa_x)(Zr_0.60Ti_0.40)O₃ (PLZT x/60/40, x?=?at.%) ceramics were prepared by using high energy mechanical ball milling followed by cold isostatic pressing (CIP), investigated for their micro-structural, dielectirc, ferroelectric and piezoelectric properties. Mechanical activation results in the highly reactive nature of the nano size milled PLZT powders, which enables the partial perovskite phase formation, confirmed by room temperature XRD patterns. CIP leads to a higher density with a closely packed dense microstructure of sintered PLZT ceramics shown in SEM images. The grain size of PLZT x/60/40 ceramics was found to be decreasing with increasing La³⁺ content. The highest relative density of ~?97% was found to be for PLZT 8/60/40 ceramics with grain size of ~?1.35 µm. The PLZT 8/60/40 system also shows the highest dielectric constant of ~?1976, remnant polarization of 29.1 µC/cm², piezoelectric coefficients (d₃₃?\(~ \cong ~\)?570 pC/N, g₃₃?\(~ \cong ~\)?28.03?×?10^?3 Vm/N) and electromechanical coupling factors (k_p?=?k₃₃?=?64.1% and k₃₁?=?54%). The elastic compliances for the PLZT x/60/40 ceramics were also obtained.     

Phase transformations during the synthesis and sintering of Y<Subscript>2 − <Emphasis Type="Italic">x</Emphasis></Subscript>Yb<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>O<Subscript>3</Subscript> nanopowders

The formation of an Y₂O₃-Yb₂O₃ solid solution (8 mol % Yb₂O₃) during the thermal decomposition of (Y,Yb)₂(CO₃)₃ · 2H₂O mixed carbonates obtained by coprecipitation from a nitrate solution has been studied by X-ray diffraction, thermal analysis, and optical microscopy. The results demonstrate that the formation of a cubic yttria-based solid solution begins in the range 470–500°C and reaches completion at temperatures above 1100°C. The unit-cell parameter a of the cubic solid solution and the X-ray density of the corresponding ceramic are 10.5910 Å and 5.349 g/cm³, which corresponds to the intended chemical composition of the isovalent substitutional solid solution: Y_1.84Yb_0.16O₃.     

Synthesis and study of structural,dielectric, magnetic and magnetoelectric properties of K<Subscript>0.5</Subscript>Na<Subscript>0.5</Subscript>NbO<Subscript>3</Subscript>–CoMn<Subscript>0.2</Subscript>Fe<Subscript>1.8</Subscript>O<Subscript>4</Subscript> composites

Magnetoelectric (ME) composites consisting of K_0.5Na_0.5NbO₃ (KNN) as ferroelectric phase and CoMn_0.2Fe_1.8O₄ (CMFO) as ferrite phase with general formula (x) CoMn_0.2Fe_1.8O₄–(1???x) K_0.5Na_0.5NbO₃ (x?=?10, 20, 30, 40 and 50 wt%) were synthesized using solid state reaction method. X-ray diffraction analysis asserts the existence of component phases including spinel phase of CMFO and orthorhombic phase of KNN. Field emission scanning electron microscopy has been used for studying the morphology and calculation of average grain size. The temperature dependent dielectric properties including dielectric constant (\(\varepsilon ^{\prime}\)) and dielectric loss (tan δ) at different frequencies has been studied and both are found to increase with incorporation of CMFO. Magnetic hysteresis loops have been measured at temperatures of 300 and 5 K. Variation of magnetization versus temperature has been studied in field cooled and zero field cooled modes. Polarization versus electric field (P–E) hysteresis loops are obtained at room temperature indicating presence of ferroelectric ordering in the composites at room temperature. The remnant polarization (2P_r) and coercive field (2E_c) are found to decrease linearly with incorporation of CMFO. ME voltage coefficient (α_ME) has been measured. The maximum value of α_ME is found to be 5.941 mV/cm-Oe for 10% CMFO–90% KNN bulk composite.     

Valence state of atoms in the perovskite-like phase Sr<Subscript>x</Subscript>Cu<Subscript>3</Subscript>V <Subscript>4</Subscript>O<Subscript>12</Subscript> (<Emphasis Type="Italic">x</Emphasis> = 0.67−1.0) and its properties

We report the first synthesis, at high pressure and temperature (p = 6.0?8.0 GPa, t = 1000°C), of Sr_xCu₃V₄O₁₂ (x = 0.67?1.0), a cation-deficient perovskite-like phase of variable composition (sp. gr. Im \(\bar 3\), Z = 2). Using x-ray photoelectron spectroscopy, we have determined the binding energies and valence states of atoms in Sr_xCu₃V₄O₁₂. The stoichiometric composition of this phase can be represented by the chemical formula Sr²⁺Cu²⁺Cu ₂ ⁺ (V ₂ ⁵⁺ V ₂ ⁴⁺ )O₁₂. Air exposure leads to the formation of SrCO₃ and Sr(OH)₂ on its surface and to the oxidation of univalent copper and tetravalent vanadium. According to IR spectroscopy data, the penta-and tetravalent vanadium in the high-pressure phase is in octahedral oxygen coordination. The electrical conductivity, magnetic susceptibility, thermal properties, and ion selectivity of this compound have been investigated.     

Synthesis of Y<Subscript>3</Subscript>Al<Subscript>5</Subscript>O<Subscript>12</Subscript>:Ce<Superscript>3+</Superscript> phosphor in the Y<Subscript>2</Subscript>O<Subscript>3</Subscript>–Al metal–CeO<Subscript>2</Subscript> ternary system

Garnet phosphor Y₃Al₅O₁₂:Ce³⁺ is prepared in the Y₂O₃–Al metal–CeO₂ ternary system by the solid-state reaction method in the air. For the first time, metal Al is used as a source of aluminum for the reaction instead of traditional oxide Al₂O₃. It is shown that the chemical reaction can be realized at lower temperatures and without use of special reducing atmosphere. The structural and spectroscopic properties of the prepared powder phosphor are very close to those earlier reported for the Y₃Al₅O₁₂:Ce³⁺ single crystal.     

Synthesis and properties of LaNi<Subscript>1−<Emphasis Type="Italic">x</Emphasis></Subscript>Fe<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>O<Subscript>3−δ</Subscript> as cathode materials in SOFC

The synthesis of LaNi_{1− x} Fe _x O_3−δ (LNF) perovskites with x = 0.0–1.0, for use as cathode materials for an IT-SOFC, was investigated using four combustion methods, Water Citrate (WC), Modified Water Citrate (MWC), Nitric Citrate (NC), and Modified Nitric Citrate (MNC). The structures and homogeneities of the synthesized powders were examined using an XRD, and the particle sizes were examined using an SEM and a particle size analyzer. All four combustion methods gave the single phase perovskites with the same structure. The main difference was shown in a particle size that the smallest to the largest sizes were obtained from MNC, MWC, NC, and WC, respectively. In this LNF series, as x is 0–0.5, the crystal structure is cubic and rhombohedral at the calcination temperature of 700 and 900 °C, respectively. Further investigation indicated that the cubic structure changed to rhombohedral structure at 900 °C, and was stable up to 1200 °C. As x is 0.6–1.0, the crystal structure is in orthorhombic phase when calcined between 700 and 1000 °C. This orthorhombic phase decomposed above 1100 °C. From the XRD and SEM–EDX results, LaNi_0.6Fe_0.4O_3−δ (LNF64) has a good chemical compatibility with 8YSZ from room temperature up to 900 °C. In addition, its thermal expansion coefficient is 13.2 × 10⁻⁶ K⁻¹ close to that of 8 mol% Y₂O₃ (8YSZ). Therefore, LNF64 also has a good physical compatibility with 8YSZ.     

Chemical,morphological, structural,optical, and magnetic properties of Zn<Subscript>1−x</Subscript>Nd<Subscript>x</Subscript>O nanoparticles

In the present investigation, we made an endeavor to fabricate the ZnO nanoparticles and achieved the tunable properties with Nd doping. The Nd-doped ZnO nanoparticles were characterized via X-ray diffraction (XRD), Raman, and X-ray photoelectron spectroscopy (XPS) studies that confirmed the successful doping of Nd ions in the ZnO crystal lattice without amending its hexagonal phase. The particle morphology revealed nearly spherical particles with uniform size distribution. The band gap of these samples was determined using diffuse-reflectance spectra (DRS) and was found to vary from 3.17 to 3.21 eV with increasing Nd concentration. A broad and intense emission band at 1083 nm for Nd doped ZnO nanoparticles is observed and is assigned to corresponding emission transition ⁴F_3/2?→?⁴I_11/2 of Nd³⁺ ions. Furthermore, the magnetic studies indicate that the Nd doping altered the magnetic behavior of nanocrystalline ZnO particles from diamagnetic to ferromagnetic at 300 K and that the magnetization of these samples decreased with increasing Nd concentration. The tunable optical band gap as well as room-temperature ferromagnetism of these samples may find applications in both optoelectronics and spintronics.     

Tunable luminescence and energy transfer properties in Ca<Subscript>2−x</Subscript>NaMg<Subscript>2</Subscript>V<Subscript>3</Subscript>O<Subscript>12</Subscript>:xEu<Superscript>3+</Superscript> phosphors

Novel broadband luminescence phosphors Ca_2?xNaMg₂V₃O₁₂:xEu³⁺ have been successfully prepared via the conventional high-temperature solid-state reaction. The effects of concentrations of doped Eu³⁺ and introducing Li⁺, K⁺ on the luminescent properties of phosphor were studied. X-ray diffraction, GSAS structural refinement and photoluminescence spectra were used to characterize the samples. The refinement data ensured where the doped Eu³⁺ ions occupied the lattice site in the host. Under 355 nm excitation, the emission peak of Ca₂NaMg₂V₃O₁₂:Eu³⁺ phosphors are located at 610 nm (red) ascribed to the electric dipole transition of Eu³⁺ from ⁵D₀ → ⁷F₂. In the range of 400–575 nm, Ca₂NaMg₂V₃O₁₂:Eu³⁺ phosphors have broad emission bands attributed to charge transfer of \({\text{VO}}_4^{3 - }\) group. Energy transfer mechanism, energy transfer efficiency and critical distance (R_c) of \({\text{VO}}_4^{3 - }\) → Eu³⁺ would be analyzed. The emitting color of Ca₂NaMg₂V₃O₁₂:Eu³⁺ could be tunable from blue-green to near white light.