Sintering behavior and microstructure of (1-x)MgAl2O4-xMg2TiO4 spinel solid solutions prepared by isostructural heterogeneous nucleation

Er‐Doped MgAl2O4 Nanofilms Enabling Highly Efficient Near‐Infrared Electroluminescence from the Silicon‐Based MOS Devices Fabricated by Atomic Layer Deposition

“…Therefore, Er 3+ ions mainly substitute the Mg 2+ ions in the spinel lattice and create one positively charged defect $$Er_{Mg}^ \cdot $$ in the system, while a charge compensation mechanism is required. [ 21,22 ] However, previous research reported the Er 3+ ions could replace not only the tetrahedral positions of Mg 2+ ions but also the octahedral positions of Al 3+ ions, due to the defect accumulation in the spinel structure. [ 23,24 ] Particularly, due to the cluster of Frenkel defect pairs in MAO spinel, the occupation of cations (Mg 2+ or Al 3+ ) at diverse sites is changed and the O interstitials recombine with the vacancies, which result in the structure transformation from ordered spinel to disordered spinel and further to disordered rock‐salt.…”

“…The transition of MAO nanolaminates into spinel structure is a continuous process of ion inter‐diffusion involving spinelisation and densification, the film thickness was found to decrease slightly after the annealing below 1000 °C, and significantly increase after the annealing at 1100–1150 °C (see Figure S1b, Supporting Information). When the annealing temperature exceeds 1100 °C, the surface of the nanofilm exhibits high microscopic dimensions and spinelisation, [ 22 ] due to the grain aggregation caused by the ion dispersion in the microstructural defects and grain boundaries, which could affect the carrier injection of the device. In this case, the MAO:Er nanofilms are prone to forming cation vacancies, enhancing the ion diffusion and affecting the optoelectronic properties.…”

Crystallization behavior and crystal characterization of V-spinel in vanadium slag via in situ separation: displacement mechanism of V and Ti

“…And the lattice of V-spinel gradually expands during the replacement process, indicating that the Ti doping in V-spinel causes lattice distortion and the degree of lattice distortion increases with the increase of Ti doping. 31…”

“…And the lattice of V-spinel gradually expands during the replacement process, indicating that the Ti doping in V-spinel causes lattice distortion and the degree of lattice distortion increases with the increase of Ti doping. 31 Hence, TiO 2 in vanadium slag plays a dual role. On one hand, increasing TiO 2 content enhances the activity of Ti in vanadium slag and lowers the viscosity of the slag phase, 32 which is advantageous for the crystallization of V-spinel.…”