Dow Science Complex 232
M.S., Physics, University of Sofia, Bulgaria, 1983
Ph.D., Physics, University of Sofia, Bulgaria, 1991
- Applied crystallography
- X-ray (synchrotron) diffraction
- 3-D structure determination and modeling
Current Research Projects
- Properties of materials are predetermined by the atomic-scale structure. For example, diamonds are hard, transparent and expensive. Graphite is black, soft and cheap. Both are pure carbon though; the difference comes from the different arrangament of carbon atoms. It is a tetrahedral network in diamond and a stack of hexagonal layers in graphite. Dr. Petkov's research aims at determining the 3D atomic-scale structure of materials by x-ray diffraction and computer simulations. Research is done at CMU and synchrotron radiation facilities. Mostly, a non-traditional experimental approach, that of atomic pair distribution function analysis, is employed. Traditional crystallography (Rietveld) is done as well. Materials of current interest include glasses (metallic, silicate, phosphate, germanate, fast conductors), liquids (water), polymers (dendrimers), composites (inorganic/organic), nanoporous zeolites and carbons, ceramics (titanates, zirconates), catalysts (Mo, Au and Pt based), nanoparticles (metallic and inorganic), data storage media (optical: Ge-Sb-Te; magnetic: Pt/Pd/Fe), disordered ferro and ferri magnets (transition & rare earth metals based), and others. Funding sources include NSF, DoE, ARL and CMU.
- V. Petkov, et al. "Size, Shape, and Internal Atomic Ordering of Nanocrystals by Atomic Pair Distribution Functions: A Comparative Study of γ-Fe2O3 Nanosized Spheres and Tetrapods." J. American Chemical Society, 131, 14262-14266 (2009).
- V. Petkov et al "Atomic-scale structure of nanocrystals by high-energy X-ray diffraction and atomic pair distribution function analysis: Study of Fe-Pd nanoparticles", J. Phys. Chem. C 111, 714 (2007).
- V. Petkov et al "Atomic-scale structure of Ba/Sr-Ti-O ceramics" Chem. Mat. 18, 814 (2006).
- V. Petkov et al "3-D structure of gold nanoparticles in water by x-ray diffraction and computer simulations" Phys. Rev. B 72, 195402 (2005).
- V. Petkov et al "3-D structure of nanocomposites from atomic pair distribution function analysis: study of polyaniline and PANI & vanadium pentoxide", J. Am. Chem. Soc. 127, 8805 (2005).
- V. Petkov et al "Structure beyond Bragg: study of vanadium pentoxide nanotubes" Phys. Rev. B 69, 085410 (2004).
- V. Petkov et al "Positional disorder of Ba in the thermoelectric germanium clathrate: Ba6Ge25" Solid. State Comm. 127, 43 (2003).
- V. Petkov et al "Structure of intercalated Cs in zeolite ITQ-4: an array of metal ions and correlated electrons confined in a pseudo-1D host" Phys. Rev. Lett. 89, 075502 (2002).