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Solid-state reaction method was employed to synthesize Co2+-doped SrMg2(PO4)2 nanopowder and characterized by different techniques to study the structural, morphological, optical, and photoluminescence effects. X-ray diffraction (XRD) analysis revealed that prepared nanopowder structure is monoclinic, and lattice parameters were evaluated. The average crystallite size, micro strain, and dislocation density were calculated and compared with Williamson-Hall method. The morphology of prepared sample was analyzed by SEM images and grain size obtained in nano range. EDS spectrum confirms the presence of desired elements of as prepared sample. The optical and EPR data exhibits distorted octahedral site symmetry of dopant with host material. Photoluminescence (PL) emission spectrum of prepared nanopowder exhibits a single broad band in visible region which represents bright blue color. CIE chromaticity coordinates, and CCT were found from emission spectrum. FTIR spectrum shows vibrational bands related to phosphates, P-O–H, and hydroxyl ions. [ABSTRACT FROM AUTHOR]

A simple solution technique was used for the synthesis of Co2+-doped ZnCdO nanopowder. A number of investigation methods have been done on the synthesized powder to study the structural, morphological, and photoluminescence properties. X-ray diffraction (XRD) studies revealed that ZnO is in a hexagonal phase and CdO is in a cubic phase when the samples were calcined at 650°C for 2 h by raising the temperature at the speed of 15°/min. Irregular-shape grains were observed from the scanning electron microscopy (SEM) images. Energy dispersive X-ray analysis (EDAX) indicated the existence of doped Co species and constituent metal ions. The bands at 417 and 460 cm–1 confirmed the presence of ZnO and CdO molecules by Fourier transform infrared spectroscopy studies. From optical absorption studies, Dq, B, and C (crystal field parameter and inter-electronic repulsion parameters) were evaluated and found to be 980, 940, and 3800 cm–1, thus confirming the doped Co2+ ions are in octahedral symmetry. Photoluminescence studies showed the emission peaks in the blue region at an excitation wavelength of 360 nm. CIE chromaticity coordinates were estimated at x = 0.1577, y = 0.0771. [ABSTRACT FROM AUTHOR]

Co2+ doped strontium zinc phosphate (SZP) nanophosphor is prepared by solution combustion method. The synthesized nanophosphor is studied by structural and spectral characterizations XRD, SEM with EDS, FT-IR, Optical absorption, EPR and Photoluminescence. X-ray diffraction pattern confirmed a monoclinic crystal phase with a crystallite size of 57 nm with the help of Debye Scherrer's formula. Morphological investigations indicate nanoflakes structure with average particle size determined in the nano range. EDS spectrum showed the existence of Strontium (Sr), Zinc (Zn), Phosphorus (P), Oxygen (O) and Cobalt (Co) in the synthesized sample. FTIR spectrum exhibited different vibrational bands corresponding to PO43−, P-O-P and other modes. Crystal field and inter-electron repulsion parameters are evaluated as Dq = 980, B = 920 and C = 3900 cm−1. Comparing optical and EPR spectra confirms the inclusion of Co2+ ions in octahedral site geometry and covalent nature coupling with its host lattice. The evaluated photometric parameters such as CIE coordinates and Colour Correlated Temperature (CCT) values indicate that prepared Co2+ doped SZP nanophosphor is potentially good for white light emitting diodes and solid state lightening. [ABSTRACT FROM AUTHOR]

Solid-state reaction synthesis produced VO2+ -doped Li2Ba3(P2O7)2 pyrophosphate nanopowder at ambient temperature. The produced sample was characterized by powder x-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS), high-resolution transmission electron microscopy (HR-TEM), Fourier-transform infrared spectroscopy (FT-IR), Raman spectroscopy, UV-visible spectroscopy, electron paramagnetic resonance (EPR), and photoluminescence (PL) techniques. Powder XRD confirmed the preservation of an orthorhombic crystal structure of the sample with an average crystallite size of 34.2 nm. In addition, lattice cell parameters and internal lattice strain were evaluated. SEM and HR-TEM images revealed that a tiny agglomeration of stone-like particles appeared in the sample and also evaluated particle size distributions. FT-IR and Raman spectra exhibited characteristic vibrational modes of phosphate (PO43−) ions along with other bands. Optical absorption spectrum of the VO2+ -doped sample exhibited three characteristic peaks at 831, 635, and 416 nm. Furthermore, crystal and tetragonal field parameters were determined as Dq = 1574, Ds = − 2903, and Dt = 664 cm−1. From the EPR spectrum, calculated spin Hamiltonian parameters were g ‖ = 1.954, g ⊥ = 1.977, A ‖ = 284 × 10−4 cm−1 and A ⊥ = 53 × 10−4 cm−1. Optical and EPR spectra revealed that VO2+ ions have tetragonal distortion octahedral site symmetry and have a moderate covalent nature with ligands. Using the PL spectrum, the CIE chromaticity coordinates were determined to be in the yellowish-green region appropriate for LEDs and lighting systems. [ABSTRACT FROM AUTHOR]

SrZn2(PO4)2:Cu2+ nanophosphor was synthesized via a solution combustion route utilizing nitrate-based precursors. Comprehensive analysis was conducted to determine the phase identification, crystal structure, crystallite size, sample morphology, vibrational bands, bonding nature, dopant site environment, and emission properties. X-ray diffraction analysis revealed a monoclinic crystal structure with average crystallite size of 72 nm, while morphological characterization indicated an anisotropic stone-like structure with particle size in the nano range. The infrared (IR) spectrum highlighted different vibrating modes corresponding to functional groups including PO43−and P–O–P in the phosphor compound. Electron paramagnetic resonance (EPR) and absorption studies revealed characteristic d–d transitions, confirming tetragonal distortion in the octahedral symmetry of Cu ions with the host lattice and indicating covalent bonding. The photoluminescence spectrum exhibited enhanced emission in the blue region, and the CIE chromatic coordinates and color correlation temperature (CCT) indicated that the prepared material has application potential in blue light-emitting devices and display devices. [ABSTRACT FROM AUTHOR]

CuO, MnO and CuMnO nanomaterials have been prepared using the chemical precipitation method. The structure of the nanomaterials has been confirmed using XRD analysis. Metal oxide vibrations have been identified and assigned to the vibrational band. The morphology of the prepared nanomaterials has been investigated in the SEM images. The optical band of the materials has been calculated using Tauc’s relation from the UV-Vis spectrum. The photocatalytic nature of the prepared nanomaterials has been studied against Congo red and Malachite green dyes. [ABSTRACT FROM AUTHOR]