Structure of ball-milled ZrO_2 and ZrO_2 -10 mol % Y_2O_3 powders revealed by HRTEM image processing

High-resolution transmission electron microscope (HRTEM) image processing analysis is used to analyse and to compare the process of ball milling in pure ZrO_2 powders and in ZrO_2-10 mol % Y_2O_3 powders. Applying HRTEM image processing to the grain boundary region and other defects, we are able to observe, at the atomic level, a possible sequence of alloying and transition that occur at the grain boundary, in the overlapping layers and on the stacking faults

Otkrivanje strukture kuglama mljevenih prahova ZrO2 I ZrO2 -10 mol % Y2O3 obradom slika HRTEM

High-resolution transmission electron microscope (HRTEM) image processing analysis is used to analyse and to compare the process of ball milling in pure ZrO2 powders and in ZrO2-10 mol % Y2O3 powders. Applying HRTEM image processing to the grain boundary region and other defects, we are able to observe, at the atomic level, a possible sequence of alloying and transition that occur at the grain boundary, in the overlapping layers and on the stacking faults.Primijenili smo analizu obradom slika iz transmisijskog elektronskog mikroskopa visokog razlučivanja (HRTEM) radi usporedbe procesa mljevenja kuglama čistog praha ZrO2 i praha ZrO2-10 mol % Y2O3. Primjenom obrade slika HRTEM za granične dijelove zrnaca i za druge defekte, uspjeli smo, na atomskoj razini, opažati moguće sljedove tvorbe slitina i prijelaza koji se dešavaju na granicama zrnaca, u preklopima slojeva i u pogreškama gomilanja

Otkrivanje strukture kuglama mljevenih prahova ZrO2 I ZrO2 -10 mol % Y2O3 obradom slika HRTEM

High-resolution transmission electron microscope (HRTEM) image processing analysis is used to analyse and to compare the process of ball milling in pure ZrO2 powders and in ZrO2-10 mol % Y2O3 powders. Applying HRTEM image processing to the grain boundary region and other defects, we are able to observe, at the atomic level, a possible sequence of alloying and transition that occur at the grain boundary, in the overlapping layers and on the stacking faults.Primijenili smo analizu obradom slika iz transmisijskog elektronskog mikroskopa visokog razlučivanja (HRTEM) radi usporedbe procesa mljevenja kuglama čistog praha ZrO2 i praha ZrO2-10 mol % Y2O3. Primjenom obrade slika HRTEM za granične dijelove zrnaca i za druge defekte, uspjeli smo, na atomskoj razini, opažati moguće sljedove tvorbe slitina i prijelaza koji se dešavaju na granicama zrnaca, u preklopima slojeva i u pogreškama gomilanja

Primjenjivost različitih metoda analize profila linija XRD za ocjenjivanje veličine zrnaca i mikronaprezanja u tankim slojevima volframa

Different methods of X-ray diffraction line profile analysis (XRDLPA) are used to study microstructural parameters such as crystallite size (diffracted domain size), microstrain and texture in tungsten thin films deposited on glass by DC magnetron sputtering at different substrate temperatures and at different working-gas pressures. The whole-pattern analysis within the Rietveld method, the "single-line" method and "double Voigt" method (equivalent to the Warren-Averbach method) are applied and mutually compared. In addition, the results obtained by the Scherrer method are also discussed. The line broadening has been found to be isotropic, supporting the reliability of usage of the Rietveld method in the size-microstrain extraction.Primijenili smo različite metode za analizu profila linija rendgenske difrakcije radi proučavanja mikrostrukturnih parametara, kao što su veličina kristalita (veličina difrakcijskih domena), mikronaprezanja i struktura u tankim slojevima volframa naparenim na staklo magnetronskim DC rasprašivanjem pri različitim temperaturama podloge i radnim tlakovima plina. Primijenili smo cjelovitu analizu spektara Rietveldovom metodom, metodom “jedne linije” i metodom “dvo-Voigta” (jednakovaljanog metodi Warrena-Averbacha) i usporedili ih. Nadalje, raspravljamo i rezultate dobivene Scherrerovom metodom. Nalazimo da je širenje linija izotropno, što potvrđuje pouzdanost primjene Rietveldove metode za izvođenje veličine i mikronaprezanja

Primjenjivost različitih metoda analize profila linija XRD za ocjenjivanje veličine zrnaca i mikronaprezanja u tankim slojevima volframa

Different methods of X-ray diffraction line profile analysis (XRDLPA) are used to study microstructural parameters such as crystallite size (diffracted domain size), microstrain and texture in tungsten thin films deposited on glass by DC magnetron sputtering at different substrate temperatures and at different working-gas pressures. The whole-pattern analysis within the Rietveld method, the "single-line" method and "double Voigt" method (equivalent to the Warren-Averbach method) are applied and mutually compared. In addition, the results obtained by the Scherrer method are also discussed. The line broadening has been found to be isotropic, supporting the reliability of usage of the Rietveld method in the size-microstrain extraction.Primijenili smo različite metode za analizu profila linija rendgenske difrakcije radi proučavanja mikrostrukturnih parametara, kao što su veličina kristalita (veličina difrakcijskih domena), mikronaprezanja i struktura u tankim slojevima volframa naparenim na staklo magnetronskim DC rasprašivanjem pri različitim temperaturama podloge i radnim tlakovima plina. Primijenili smo cjelovitu analizu spektara Rietveldovom metodom, metodom “jedne linije” i metodom “dvo-Voigta” (jednakovaljanog metodi Warrena-Averbacha) i usporedili ih. Nadalje, raspravljamo i rezultate dobivene Scherrerovom metodom. Nalazimo da je širenje linija izotropno, što potvrđuje pouzdanost primjene Rietveldove metode za izvođenje veličine i mikronaprezanja

On the applicability of different methods of XRD line profiles analysis in estimating grain size and microstrain in tungsten thin films

Different methods of X-ray diffraction line profile analysis (XRDLPA) are used to study microstructural parameters such as crystallite size (diffracted domain size), microstrain and texture in tungsten thin films deposited on glass by DC magnetron sputtering at different substrate temperatures and at different working-gas pressures. The whole-pattern analysis within the Rietveld method, the "single-line" method and "double Voigt" method (equivalent to the Warren-Averbach method) are applied and mutually compared. In addition, the results obtained by the Scherrer method are also discussed. The line broadening has been found to be isotropic, supporting the reliability of usage of the Rietveld method in the size-microstrain extraction

Structure of ball-milled ZrO_2 and ZrO_2 -10 mol % Y_2O_3 powders revealed by HRTEM image processing

High-resolution transmission electron microscope (HRTEM) image processing analysis is used to analyse and to compare the process of ball milling in pure ZrO_2 powders and in ZrO_2-10 mol % Y_2O_3 powders. Applying HRTEM image processing to the grain boundary region and other defects, we are able to observe, at the atomic level, a possible sequence of alloying and transition that occur at the grain boundary, in the overlapping layers and on the stacking faults

On the applicability of different methods of XRD line profiles analysis in estimating grain size and microstrain in tungsten thin films

Different methods of X-ray diffraction line profile analysis (XRDLPA) are used to study microstructural parameters such as crystallite size (diffracted domain size), microstrain and texture in tungsten thin films deposited on glass by DC magnetron sputtering at different substrate temperatures and at different working-gas pressures. The whole-pattern analysis within the Rietveld method, the "single-line" method and "double Voigt" method (equivalent to the Warren-Averbach method) are applied and mutually compared. In addition, the results obtained by the Scherrer method are also discussed. The line broadening has been found to be isotropic, supporting the reliability of usage of the Rietveld method in the size-microstrain extraction

Interplay between the structural and magnetic probes in the elucidation of the structure of a novel 2D layered V_4O_4(OH)_2(O_2CC_6H_4CO_2)_4·DMF

The title compound has been synthesized under solvothermal conditions by reacting vanadium(V) oxytriisopropoxide with terephthalic acid in N,N-dimethylformamide. A combination of synchrotron powder diffraction, infrared spectroscopy, scanning and transmission electron microscopy, thermal and chemical analysis elucidated the chemical, structural and microstructural features of new 2D layered inorganic-organic framework. Due to the low-crystallinity of the final material, its crystal structure has been solved from synchrotron X-ray powder diffraction data using a direct space global optimization technique and subsequent constraint Rietveld refinement. [V_4O_4(OH)_2(O_2CC_6H_4CO_2)_4•DMF] crystallizes in the monoclinic system (space group P2/m (No. 10)); cell parameters: a = 20.923(4), b = 5.963(4), c = 20.425(1)Å, β = 123.70(6)º, V = 2120.1(9)Å^3, Z = 2. The overall structure can be described as an array of parallel 2D layers running along [-101] direction, consisting of two types of vanadium oxidation states and coordination polyhedra: face-shared trigonal prisms (V^4+) and distorted corner-shared square pyramids (V^5+). Both configurations form independent parallel chains oriented along the 2-fold symmetry crystallographic b-axis mutually interlinked with terephthalate ligands in a monodentate mode perpendicular to it. The morphology of the compound exhibits long nanofibers, with the growth direction along the layered [-101] axis. The magnetic susceptibility measurements show that the magnetic properties of V_4O_4(OH)_2(O_2CC_6H_4CO_2)_4•DMF can be described by a linear antiferromagnetic chain model, with the isotropic exchange interaction of J = −75 K between the nearest V^4+ neighbours of S = 1/2

Long cycle life of CoMn2O4 lithium ion battery anodes with high crystallinity

CoMn2O4 nanomaterials are prepared by a low temperature precipitation route employing metal acetates and NaOH. Structural changes, induced by different annealing temperatures, are comprehensively analyzed by X-ray powder diffraction and Raman spectroscopy. With rising annealing temperature the crystal lattice of CoMn2O4 undergoes changes ; AO4 tetrahedra expand due to thermally induced substitution of Co2+ by larger Mn2+ metal ions on the A-site of the spinel structure, while in contrast, BO6 octahedra shrink since the B-site becomes partially occupied by smaller Co3+ metal ions on account of the migrated Mn ions. CoMn2O4 particle sizes are easily fine-tuned by applying different annealing temperatures ; the particle size increases with increasing annealing temperature. During the battery operation, pulverization and reduction of particle sizes occurs regardless of the initial size of the particles, but the degree of division of the particles during the operation is dependent on the initial particle properties. Thus, contrary to the common assumption that nanostructuring of the anode material improves the battery performance, samples with the largest particle sizes exhibit excellent performance with a capacity retention of 104% after 1000 cycles (compared to the 2nd cycle)