Microwave-assisted hydrothermal method was applied to synthesize BaZr 1−x Hf x O 3 , (BZHO) solid solutions at low temperature, 140 • C, and relative short times, 160 min. The detailed features of the crystal structure, at both short and long ranges, as well as the crystal chemistry doping process, are extensively analysed. X-ray diffraction measurements and Raman spectroscopy have been used to confirm that pure and Hf-doped BZO materials present a cubic structure. Extended X-ray absorption fine structure (EXAFS) indicate that Hf 4+ ions has replaced the Zr 4+ ions on the 6-fold coordination and a subsequent change on the Ba 2+ 12-fold coordination can be sensed. X-ray absorption near-edge spectroscopy (XANES) measurements reveal a local symmetry breaking process, associated to overlap of the 4d -2p and 5d -2p orbitals of Zr-O and Hf-O bonds, respectively. Field emission gun (FE-SEM) and high resolution transmission electron microscope (HRTEM) show the mesocrystalline nature of self-assembled BZHO nanoparticles under dodecahedron shape. In addition were performed first principle calculations to complement experimental data. The analysis of the band structures and density of states of undoped BZO and doped BZHO host lattice allow a deep insight on the main electronic features. The theoretical results help us to find a correlation between simulated and experimental Raman modes and allow a more substantial interpretation of crystal structure.

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A study of the optical properties and influence of Eu ions on a hybrid inorganic system synthesized by a microwave-assisted hydrothermal method.

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