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Selected PublicationS

Solid state chemistry of novel energy-re-lated materials, such as new battery, thermoelectric, and strongly correlated

electron materials, is the focus of our research.

The Design of Advanced Materials assumes an understanding of the correlation between chemical composition, crystal structure, crys-tallite size and shape, and physical/chemical properties. Although it is not possible yet to reliably predict materials’ properties, there are often crystal structure motives, special

features in band structures or in atom spin states which are favorable for a property to emerge. Therefore, the ability to design ratio-nally new compounds is crucial for discovery of materials with advanced properties. New synthetic methodology developed in our group enables for the preparation of novel materials in a predictable way.

Battery Materials. The development of cheap-er and safer batteries with higher energy den-sities for vehicular and large scale energy stor-age applications is primarily hindered by the properties of the cathode materials. In order to drastically increase battery energy densi-ties we perform the systematic investigation of the possibility of two Li per one transitional metal atom cycling in intercalation chemistry based cathode materials. For the first time electrochemical cycling of the Fe3+/Fe4+ redox couple at 4.5 V was demonstrated for a novel tunnel LiFeO2 polymorph.

Strongly Correlated-electrons Materials. In a special class of transitional metal com-pounds electron–electron interaction results

in a variety of physical properties important from fundamental and technological points of view: high temperature superconductivity, multiferroic, thermoelectric, heavy fermion metallic behavior, and colossal magnetore-sistance. Investigation of structure-property relationships for these compounds provides deep insights into correlated-electron behav-ior, approximate to possibility of design of materials with desired properties.

Density Functional Theory is used to calculate the electronic structure of complex systems. In our group theoretical calculations are used

to calculate electronic band structures, Fermi surfaces and total energies of magnetically ordered states. This allows deeper under-standing of measured properties. Theoretical properties predictions are also used to iden-tify phases of interest for further synthesis.

Students are trained in the areas of inorganic synthesis, electrochemistry, crystallography, magnetism, and various characterization techniques. Expertise in synthetic methods and characterization techniques will allow the students to become versatile scientists, well equipped with the technical prerequisites necessary for future independent careers.

Crystal structure model of tunnel LiFeO2. FeO6 octahedra are highlighted. Li atoms are shown as yellow spheres.

Structure refinement of high resolution synchro-tron powder X-ray diffraction data collected at Argonne National Laboratory.

Structure refinement of high resolution synchrotron powder X-ray diffraction data collected at Argonne National Laboratory.

Inorganic Materials Chemistry:

Energy MaterialsAssistAnt Professor

(b. 1974)

M.S., 1996, Moscow State Univ. (Russia);

Ph.D., 1999, Moscow State Univ. (Russia);

Postdoctoral Fellow, 2000-2001, MPI Stuttgart (Germany);

Alexander von Humboldt Foundation Postdoctoral Fellow, 2001-2003,

MPI Stuttgart (Germany);

Research Associate, 2004-09, Rutgers, The State Univ. of New Jersey.

517-355-9715, Ext. 388

Viktor V. Poltavets

Multistep soft chemistry method for valence reduction in transition metal oxides with triangular (CdI2-type) layers, C.K. Blakely, S.R. Bruno, V.V. Poltavets, Chem. Comm. 2014, 50, 2797-2800.

Low temperature high-pressure synthesis of LnNiO3 (Ln = Eu, Gd) in molten salts, J. Prakash, C. K. Blakely, V. V Poltavets, Solid State Sci. 2013, 17, 72-75.

Synthesis of Mixed-Valent α- and β- NaFe2O3 Polymorphs under Controlled Low Oxygen Pressure, S.R. Bruno, C.K. Blakely, V.V. Poltavets, J. Solid State Chem. 2012, 192, 68-74.

Synthesis of MSnO3 (M = Ba, Sr) Nanoparticles by Reverse Micelle Method and Particle Size Distribution Analysis by Whole Powder Pattern Modelling, J. Ahmed, S.R. Bruno, C.K. Blakely, V.V. Poltavets, Mater. Res. Bull. 2012, 47, 2282-2287.

Low Temperature Solvothermal Approach to the Synthesis of La4Ni3O8 by Topotactic Oxygen Deintercalation, Colin K. Blakely, Shaun R. Bruno, Viktor V. Poltavets, Inorg. Chem. 2011, 50, 6696.

Bulk Magnetic Order in a Two-Dimensional Ni1+/Ni2+ (d9/d8) Nickelate, Isoelectronic with Superconducting Cuprates, V.V. Poltavets et al., Phys. Rev. Lett. 2010, 104, 206403.

Electronic Properties, Band Structure, and Fermi Surface Instabilities of Ni1+/Ni2+ Nickelate La3Ni2O6 , Isoelectronic with Superconducting Cuprates, V.V. Poltavets et al., Phys. Rev. Lett. 2009, 102, 046405.