A microwave-assisted hydrothermal method was applied to synthesize BaZr1xHfxO3, (BZHO) solidsolutions at a low temperature, 140 1C, and relatively short times, 160 min. The detailed features of thecrystal structure, at both short and long ranges, as well as the crystal chemistry doping process, areextensively analysed. X-ray diffraction measurements and Raman spectroscopy have been used toconfirm that pure and Hf-doped BZO materials present a cubic structure. Extended X-ray absorptionfine structure (EXAFS) spectra indicate that Hf4+ ions have replaced the Zr4+ ions on the 6-foldcoordination and a subsequent change on the Ba2+ 12-fold coordination can be sensed. X-rayabsorption near-edge structure (XANES) spectroscopy measurements reveal a local symmetry breakingprocess, associated to overlap of the 4d–2p and 5d–2p orbitals of Zr–O and Hf–O bonds, respectively.Field emission scanning electron microscopy (FE-SEM) and high resolution transmission electronmicroscopy (HRTEM) show the mesocrystalline nature of self-assembled BZHO nanoparticles under adodecahedron shape. In addition first principle calculations were performed to complement theexperimental data. The analysis of the band structures and density of states of the undoped BZO anddoped BZHO host lattice allow deep insight into the main electronic features. The theoretical resultshelp us to find a correlation between simulated and experimental Raman modes and allow a moresubstantial interpretation of crystal structure.
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