This work describes a wet-processing route based on spray-freezing and subsequent lyophilization designed to obtain nanostructured ceramic/metal powders. Starting from the ceramic powder and the corresponding metal salt, a water-based suspension is sprayed on liquid nitrogen. The frozen powders are subsequently freeze-dried, calcined and reduced. The material was analyzed using X-ray diffractio...

Conventional Fourier analysis is one of the most commonly used methods for localization of missing atoms in crystal structures from powder diffraction data. A “perfect” Fourier map would require a complete set of structure factors up to a resolution of at least sin/ = 5.0 Å. In the case of powder diffraction, accessible information is limited, as compared to single crystal diffraction, mainl...

Abstract: Nanocrystalline MgAl2O4 spinel powder was synthesized using metal nitrates and a polymer matrix-based composed of sucrose and polyvinyl alcohol (PVA). The precursor and the calcined powders were characterized by simultaneous thermal analysis (STA), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscopy (SEM). According to XRD res...

The presence of multiple, neighbouring transition metals presents a challenge for powder diffraction when trying to locate individual elements in a structure. Combining the information in X-ray and neutron data in simultaneous refinements has historically been a powerful tool. However, increasingly complex compositions require more information and element contrast than two datasets can provide....