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Zinc oxide (ZnO) nanopowder samples were prepared by using co-precipitation method, with varying parametric conditions. Rietveld refinement technique is used to study the structural properties of synthesized samples. XRD and UV spectroscopy techniques have been used to characterize the samples which resemble ZnO nanostructures. Observed lattice parameters are $a=b=3.2482$ Å and $c=5.2011$ Å for sample A, $a=b=3.2500$ Å and $c=5.2062$ Å for sample B, $a=b=3.2497$ Å and $c=5.2017$ Å for sample C, $a=b=3.2550$ Å and $c=5.2122$ Å for sample D. The varying unit cell volume and axial ratio for all samples are calculated as 47.52–47.82 Å and 1.6006–1.6019. VESTA software is used to calculate the bond angles and lengths of Rietveld refinement data. UV-Vis spectroscopy analyzed the absorption, transmission, refractive index and band gap of samples for their possible use in different industrial applications.

The main objective of this research is the explanation of the replacement of feldspar limestone imported from Spain with recycled automotive glass, in order to reduce waste and promote environmental sustainability. Details and efforts of making porcelain ceramics from local raw materials such as quartz, kaolin and glass are also given. Replacing the feldspar with reclaimed automotive glass shows the effect of the Na₂O and CaO solvents contained in the glass on the sintering and crystallization of the studied porcelain. The results showed that the added glass contributes to the reduction of the density and the acceleration of the sintering process, by occupying the sites of the open spaces, observed in the samples not containing feldspars. By reaching a nonporous ratio at a temperature of 1000^∘C, the melting of the material is accelerated due to the dissolved oxides it contains, in addition to the linear shrinkage rate in samples that contain a lot of glass reaching the normal level of porcelain (about 12%) at low temperature compared to ordinary porcelain.

The study on the evolution of natural ferroan brucite (MgFe(OH)${}_2)$ was beneficial to discovering the function of brucite in the geologic cycle and directing the reasonable utilization of brucite resources. In this study, natural MgFe(OH)₂ was characterized in detail and Rietveld refinement was employed to determine the precise content and existing environment of Fe${}^{2+}$. The reaction products of MgFe(OH)₂ under various atmospheric conditions, including CO₂, O₂ and a mixed atmosphere of CO₂ and O₂ were innovatively investigated to gain insights into the evolution process and the crucial role played by Fe${}^{2+}$. Accordingly, the evolution mechanism of MgFe(OH)₂ under different atmospheres was afforded based on the characterization and molecular simulations like electron transfer and binding energy. Fe${}^{2+}$ in MgFe(OH)₂ layers could be oxidized by O₂ easily and give positive layers, CO${}_3^{2-}$ produced by CO₂ dissolving in water simultaneously was attracted to finally produce CO${}_3^{2-}$ intercalated MgFe- layered double hydroxides (MgFe-CO${}_3^{2-}$-LDHs) which could be used as adsorbents, catalysts and so on. This process was supported by thermodynamics and also the dominant evolution route due to the dynamic reason. The existence of Fe${}^{2+}$ in MgFe(OH)₂ resulted in the diversity of the evolution products. This work highlighted the composition and structure of evolution products of natural MgFe(OH)₂ under different environment as well as its possible application field.

We investigated the effect of Ni doping on the structural and electrical properties of LaCoO₃. Single phase LaCo_1-xNi_xO₃ (x = 0, 0.1, 0.3, 0.5) were synthesized using solid state reaction method. Space group, lattice constants and atomic positions were determined by Rietveld refinement of powder diffraction data. The unit cell parameters found to increase with Ni doping. Four-probe direct current conductivity measurements were also carried out to investigate transport behavior of compounds. Samples were found to exhibit temperature dependent semiconducting behavior. The drastic improvement of the room-temperature conductivity of doped samples with respect to the pure compound has been observed and explained in terms of decrease in band gap. The transport mechanism in different regions of temperature has been investigated by fitting Arrhenius and variable range hopping (VRH) models.

In the present work, Al${}^{3+}$ substituted cobalt ferrites (CoFe${}_{2-x}$Al_xO₄, $x=0.2$, 0.4, 0.6, 0.8) have been synthesized via standard solid-state reaction technique. The incorporation of Al${}^{3+}$ ions in cobalt ferrite has been shown to play an important role in modifying the magnetic properties. The room temperature (300K) ${}^{57}$Fe Mössbauer spectra reveals that the studied samples show two characteristic ferromagnetic zeeman sextets at A and B-sites at lower Al${}^{3+}$ ion concentration (i.e., up to $x=0.4$). However, a paramagnetic relaxation has been noted for higher Al${}^{3+}$ substitution (for $x=0.6$ and 0.8) samples. The dependence of the Mössbauer parameters such as isomer shift, quadrupole splitting, line width and magnetic hyperfine field on Al${}^{3+}$ ion concentration has also been noted. The variations in initial permeability over a wide frequency range (125kHz to 30MHz) at 300K have been recorded. The fairly constant values of initial permeability and the low values of the relative loss factor of the order of 10${}^{-4}$ to 10${}^{-5}$ over the wide frequency range are the important findings of the present work. The observed low values of relative loss factor at high frequencies suggest that the studied ferrites are promising materials to be used in microwave applications.

By examining the diffraction data, the microstructure of the ball-milled synthesized powder sample (${\text{Ba}}_{0.9998}$${\text{Pr}}_{0.002}$TiO₃) was characterized. Through the application of Rietveld’s powder structure refinement approach to analyze X-ray powder diffraction data of ball-milled powder mixes, structural and microstructural alterations in terms of lattice defects have been assessed in the formation of single-phase praseodymium-modified BaTiO₃. Bond lengths, bond angles, and generated locations of the ${\text{Ba}}_{0.998}$Pr₀${.}_{002}$TiO₃ ceramic have been discussed about its generated structure. X-ray diffraction with respect to the first sharp diffraction peak (FSDP) is used to study the nanostructure of void species. General equations were utilized to determine various FSDP characteristics such as interlayer separation, correlation length, nanovoid diameter and scattering vector magnitude. Although the literature reports on many properties of Pr-modified barium titanate ceramic, this sample’s quantitative analysis and nanovoid determination are presented for the first time.