Effect of the synthesis conditions on the crystal, local, and electronic structure of Ce1-x 3+ Cex 4+ AlO3 + x/2

Cerium monoaluminate Ce1-x 3+ Cex 4+ AlO3+x/2 powders with low contents of Ce4+ cations (x ∼ 0.052) were synthesized. A set of modern local structure sensitive methods of analysis, including X-ray absorption spectroscopy and Raman spectroscopy, were used to study the crystal, local, and electronic structures of the synthesized compounds. The degree of reduction and the thermal stability to oxidation of reduced powders depend not only on the reduction conditions but also on the conditions of heat pretreatment of the initial samples. It was concluded that the reaction 4CeAlO3 + O2 ↔ 4CeO2 + 2Al2O3 is reversible. © Pleiades Publishing, Ltd., 2016.