Alexander P. Nemudry is PhD, Doctor of Chemical Sciences, Director of Institute of Solid State Chemistry and Mechanochemistry SB RAS. He is a specialist in materials science, reactivity of solids, intercalation, oxygen transport, nonstoichiometric perovskites, oxygen permeable membranes, electrode materials, solid oxide fuel cells.
The main results:
It was discovered the interaction of aqueous solution of lithium salts with crystalline aluminum hydroxide (gibbsite) which proceeds through the selective intercalation of lithium ions into the interlayer space of gibbsite. The studies formed the basis of the technology of lithium extraction from natural brines and technological solutions.
It was found that the low-temperature (100–200°C) treatment of the nonsuperconducting phase of YBa2Cu3O7-δ with halogens leads to the formation of superconducting compounds by intercalation of halogens (Cl, Br, and I) into the YBCO crystal lattice.
It was shown that a significant deviation from oxygen stoichiometry in perovskite related oxides is accompanied by nanostructuring. This ensures the fast oxygen diffusion along the domain walls and high reactivity of oxides.
In the lab of A. P. Nemudry it was shown that nanostructuring related to the ferroelastic nature of perovskite with mixed ionic and electronic conductivity (MIEC). A strategy has been developed to regulate the functional properties of the MIEC oxides by doping them with ferroactive highly charged cations. Based on the developed concept, nanostructured membrane and electrode materials have been developed, which demonstrate high performance in long-term tests under operating conditions of solid oxide fuel cells (SOFC) and catalytic membrane reactors.
A novel method has been developed for the construction of detailed equilibrium “3-δ - pO2 - T” diagrams for MIEC oxides based on the determination of oxygen nonstoichiometry as a continuous function of the oxygen partial pressure.
A novel relaxation method has been developed for the study of kinetics of oxygen exchange of MIEC oxides with gas phase in which the pO2 is the precisely measured parameter. A new “isostoichiometric” approach is proposed for analyzing the kinetic data on oxygen exchange in nonstoichiometric oxides.
A.P. Nemudry is the author of 260 publications including 6 patents.