“…They also have the ability to act as intercalation, ion-exchange, magnetism, cathode, and nonlinear optical (NLO) materials [1][2][3][4][5][6][7]. In vanadates, vanadium has been found in three-, four-, five-, and six-coordinate environments.…”
Abstract:The polycrystalline Na 2 SmV 5 O 15 (NSV), a new member of the tungsten bronze (TB) family, was prepared by a mixed-oxide technique. The room-temperature X-ray diffraction (XRD) confirmed the formation of single phase compound with orthorhombic crystal structure. The scanning electron microscopy (SEM) analysis indicated that the compound has homogeneous micrograph with a uniform distribution of small grains over the entire surface of the sample. The analysis of impedance spectra of NSV in a low-temperature range (100 ℃ to 100 ℃) at different frequencies exhibited interesting electrical properties like the contribution of bulk effect in conduction process. The study of imaginary part of the impedance at different temperatures showed existence of relaxation peak with its shift towards higher frequency on increasing temperature. This suggested the presence of frequency and temperature dependent relaxation process in the material. The loss peak spectra were found to abide by Arrhenius law with small activation energy of 0.12 eV. The temperature dependence of AC and DC electrical conductivity ( AC and DC ) was also obtained.
“…They also have the ability to act as intercalation, ion-exchange, magnetism, cathode, and nonlinear optical (NLO) materials [1][2][3][4][5][6][7]. In vanadates, vanadium has been found in three-, four-, five-, and six-coordinate environments.…”
Abstract:The polycrystalline Na 2 SmV 5 O 15 (NSV), a new member of the tungsten bronze (TB) family, was prepared by a mixed-oxide technique. The room-temperature X-ray diffraction (XRD) confirmed the formation of single phase compound with orthorhombic crystal structure. The scanning electron microscopy (SEM) analysis indicated that the compound has homogeneous micrograph with a uniform distribution of small grains over the entire surface of the sample. The analysis of impedance spectra of NSV in a low-temperature range (100 ℃ to 100 ℃) at different frequencies exhibited interesting electrical properties like the contribution of bulk effect in conduction process. The study of imaginary part of the impedance at different temperatures showed existence of relaxation peak with its shift towards higher frequency on increasing temperature. This suggested the presence of frequency and temperature dependent relaxation process in the material. The loss peak spectra were found to abide by Arrhenius law with small activation energy of 0.12 eV. The temperature dependence of AC and DC electrical conductivity ( AC and DC ) was also obtained.
“…Since 2006, the optical properties of BNN single crystals (with sizes up to 2 ϫ 2 ϫ 3 mm 3 ) activated with trivalent lanthanide ions and grown in Na 2 B 4 O 7 flux have been examined. [34][35][36] Structural features play a crucial role in the physical properties of TTB niobates, especially their dielectric properties. In the paraelectric state, the TTB structure is expected to be centrosymmetric with space group P4/mbm.…”
Centimeter-sized single crystals of Ba 2 LaFeNb 4 O 15 were grown from a high-temperature solution by using LiBO 2 flux and a sealed platinum assembly. The obtained single crystals display the same physical properties as their ceramic counterparts. A frequency-dependent dielectric permittivity maximum was found (T m = 100 K at 5 kHz), which indicates relaxor behavior. Magnetic susceptibility measurements revealed purely paramagnetic behavior between 10 and 350 K. X-ray diffraction measurements of Ba 2 LaFeNb 4 O 15 single
“…Because the 4f electrons of RE ions are shielded by the outer 5s and 5p electrons, the intra-4f emission spectra of RE ions are characterized by narrow lines with high color purity. The emission of Sm 3+ is situated in the orange spectral region and consists of transitions from the excited 4 G 5/2 level to the ground state 6 H 5/2 and higher levels 6 H J (J > 5/2) [10][11][12]. The luminescence lines of Dy 3+ are in the 480 nm region (blue) due to the 4 F 9/2 → 6 H 15/2 transition, and in the 570 nm region (yellow) due to the 4 F 9/2 → 6 H 13/2 transition.…”
Section: Introductionmentioning
confidence: 99%
“…The color of the luminescence is close to white if a suitable ratio of B/Y obtained. Therefore, Dy 3+ doped materials may be potential two primary color phosphors [12,14,15].…”
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.