Kazan National Research Technological University, Kazan, Russia:

A. F. Dresvyannikov, Head of the Department of Electrochemical Technology, Professor, Doctor of Сhemical Sciences, e-mail: alfedr@kstu.ru
M. E. Kolpakov, Professor at the Department of Analytical Chemistry, Certification and Quality Management, Associate Professor, Doctor of Сhemical Sciences
E. A. Ermolaeva, Associate Professor at the Department of Analytical Chemistry, Certification and Quality Management, Associate Professor, Сandidate of Сhemical Sciences

The aim of the work is to study the possibility of synthesizing the Al – Cr – Mn – Fe – Co – Ni polymetallic system in aqueous solutions of metal compounds using dispersed aluminum. The synthesis of the polymetallic system based on the RedOx reaction of metal ions and aluminum in halide-containing aqueous solutions. The oxidation of aluminum during the process accompanied by the reduction of proton donors (hydrogen depolarization) and the oxidizing agent — metal ions. Using the scanning electron microscopy and Auger electron spectroscopy the morphology and elemental composition of the surface (near-surface region) of powder particles are studied. The elemental, phase, and particle size distribution of the synthesized sample of the Al – Cr – Mn – Fe – Co – Ni polymetallic system is obtained. It found that the sample consists of predominantly spherical shape particles with sizes from units to several hundred micrometers. Inside the particles there is a layered structure enclosed in a shell 100–200 nm thick. According to the results of elemental analysis, it found that the elemental composition of the particles shell is O, Fe, Co, Ni, Al, whereas in the bulk Al is predominantly contained. X-ray phase analysis showed the presence of the metal phases: -Fe, Al and the solid solutions of Cr, Mn, Fe, Co, Ni in -Fe.
This research study was funded by the Russian Foundation for Basic Research and the Government of the Republic of Tatarstan under the Project No. 18-43-160027, and it was carried out using the facilities of the Shared Knowledge Centre for Nanomaterials & Nanotechnologies.

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