Aluminothermic Synthesis of Dispersed Electrides Based on Mayenite: XRD and EPR Study.

The evolution of the structure and the phase composition of a dispersed mayenite at its interaction with metallic aluminum was studied in a temperature range from 900 to 1400 °C in both argon and air atmospheres. The aluminum loading was varied from 0 to 50 wt%. It was found that the addition of aluminum significantly affects the stability of the mayenite and other calcium aluminate phases within the studied temperature range.

Resistance Switching in Polycrystalline C12A7 Electride.

The memory (memristive) properties of an electride material based on polycrystalline mayenite (C12A7:e) were studied. The phase composition of the material has been confirmed by such methods as XRD, TEM, Raman, and infrared spectroscopy. The electride state was confirmed by conductivity measurements and EPR using a characteristic signal from F-like centers, but the peak at 186 cm, corresponding to an electride with free electrons, was not observed explicitly in the Raman spectra.

The Influence of Argon Cluster Ion Bombardment on the Characteristics of AlN Films on Glass-Ceramics and Si Substrates.

In this paper, the influence of surface modification on the characteristics and properties of AlN thin films on Si and glass-ceramics substrates is investigated. The surface modification was made at various parameters of argon cluster ions. By using XRD and Raman spectroscopy, it was shown that the obtained AlN films have a hexagonal structure with a characteristic direction of texturing along the axis and slight deviations from it.

Mayenite Synthesis from Hydroxide Precursors: Structure Formation and Active Sites on Its Surface.

We studied the formation process of a mayenite structure from hydroxide precursors in different gas media. According to X-ray diffraction data, this method allows a well-crystallized mayenite (CaAlO or C12A7) phase to be obtained at low (500-900 °C) temperatures with an insignificant impurity of CaO. It was shown that the lattice parameters for C12A7 obtained in an inert atmosphere (Ar) were lower when compared with similar samples in the air.