Ti-doped nano MgAl2O4 for white emission was synthesized by combustion method. Extrinsic Schottky defects, Al vacancies and Ti4+ dopant in Al sites, which are considered to be responsible for bluish-white emission, were observed by STEM on the surface of Ti-doped nano MgAl2O4 powder. The stabilities of the Schottky defect associates, (TiAl·-VAl''')'', were demonstrated by DFT calculation. The e...

We report here experimental results of yield strength and stress relaxation measurements of transparent MgAl2O4 nano-ceramics at high pressure and temperature. During compression at ambient temperature, the differential strain deduced from peak broadening increased significantly with pressure up to 2 GPa, with no clear indication of strain saturation. However, by then, warming the sample above ...

Al/MgAl2O4in situ metal matrix composites have been synthesized using value-added silica sources (microsilica and rice husk ash) containing ∼97% SiO2 in Al-5 wt.% Mg alloy. The thermodynamics and kinetics of MgAl2O4 formation are discussed in detail. The MgO and MgAl2O4 phases were found to dominate in microsilica (MS) and rice husk ash (RHA) value-added composites, respectively, during the ini...

Using a novel experimental procedure in the field of ceramics/materials science that is based on the precise microanalysis (scanning electron microscopy, coupled with wavelength-dispersive spectroscopy) of the phases that are present in equilibrated specimens, the solid-state compatibility relations in the subsystem MgAl2O4–CaAl4O7–CaO– MgO and the melting relationships in the subsystems MgAl2O...

High-resolution electron microscopy was employed to characterize the interface structure of a cast Al-Mg-Si-Bi-Pb aluminium(6262)-based composite reinforced by alpha alumina particles with a trace of beta alumina in order to investigate the behaviour of alloying elements in cast composites. Except for a few primary Mg2Si particles, few reaction products were detected at the interface of Al/alph...

Epitaxial thin films of ZnMn2O4, grown from an aqueous solution on (100) and (111) spinel MgAl2O4 substrates, have been topotactically reduced and leached to produce epitaxial rock salt MnO on the same substrates. The volume change accompanying the conversion of ZnMn2O4 to 2MnO associated with a loss of Zn and O2 manifests as a network of interconnected, 50-100 nm pores. The topotactic nature o...

Articles you may be interested in Perpendicular magnetic anisotropy in Ta|Co40Fe40B20|MgAl2O4 structures and perpendicular CoFeB|MgAl2O4|CoFeB magnetic tunnel junction Appl. Large enhanced perpendicular magnetic anisotropy in CoFeB/MgO system with the typical Ta buffer replaced by an Hf layer

From an interplay of atom-resolved noncontact atomic force microscopy, surface x-ray diffraction experiments, and density functional theory calculations, we reveal the detailed atomic-scale structure of the (100) surface of an insulating ternary metal oxide, MgAl2O4 (spinel). We surprisingly find that the MgAl2O4(100) surface is terminated by an Al and O-rich structure with a thermodynamically ...

Chemical looping gasification (CLG) is a promising method for the utilization of biomass to produce syngas. However, its realization is largely dependent on the use of an oxygen carrier with a high and stable reactivity in cyclic reduction and oxidation. This work focused on the improvement of reactivity and stability of CuO in chemical looping gasification via the addition of MgAl2O4 as an ine...

In this paper, the structure of Al2O3 is modified with magnesium to synthesize MgAl2O4 as an oxygen carrier (OC) support. The surface properties and structural stability of the modified support are improved by the incorporation of magnesium in the structure of the support and additionally by narrowing the pore size distribution (about 2.3 nm). Then, iron oxide is impregnated on both an Al2O3 su...