M. Samy El-Shall
 |
Professor |
Education
B.S., Cairo University
M.S., Cairo University
Ph.D., Georgetown University
Research interests
Our research interests are in the general areas of molecular clusters, gas phase and cluster polymerization, nucleation phenomena and nanostructured materials. The major goal is to gain insights as to how the properties of matter evolve as the size of a material system ranges from molecular to macroscopic dimensions. Research is under way in three areas, each involving a variety of experimental techniques (molecular beams, lasers, mass spectrometry and light scattering) with close collaboration with modern theoretical approaches.
Molecular clusters, gas phase and cluster polymerization
Molecular beam techniques are applied to synthesize different classes of weakly bound molecular clusters and metal atom-doped molecular clusters. Resonant two-photon ionization coupled with time-of-flight mass spectrometry is then applied to study the spectroscopy of size specific clusters. We are interested in measuring the size-dependent spectroscopic lineshifts and lineshapes of a particular atomic or molecular excitation in these clusters.
Read more about the cluster research.
Vapor phase homogeneous and ion-induced nucleation
Nucleation is one of the most ubiquitous and important phenomena in science and technology. It plays a central role in materials science, crystal growth, chemical processing, atmospheric science and cosmochemistry. This research area is of increasing importance to atmospheric chemistry, polar stratospheric clouds, acid rain and air pollution.
Read more about the nucleation work.
Nanostructured materials
Nanoscale particles possess several unique properties such as large surface areas, unusual adsorptive properties, surface defects and fast diffusivities. The intrinsic properties of the interior of the nanocrystals are transformed by quantum size effects. The ability to manipulate the energetics of nanocrystal surfaces at will would have many practical consequences particularly in the fields of catalysis and novel materials.
Read more about the nanoparticle research.
Publications
Moussa, S.O.; El-Shall, M.S., Fabrication of nanostructured nickel and titanium aluminides starting from elemental nanopowders. Materials Chemistry and Physics 2008, 112, 1015-1020.
Momoh, P.O.; Soliman, A.R.; Meot-Ner, M.; Ricca, A.; El-Shall, M.S., Formation of complex organics from acetylene catalyzed by ionized benzene. Journal of the American Chemical Society 2008, 130, 12848-+.
Momoh, P.O.; El-Shall, M.S., Gas phase hydration of organic ions. Physical Chemistry Chemical Physics 2008, 10, 4827-4834.
El-Shall, M.S., Polymerization in the gas phase, in clusters, and on nanoparticle surfaces. Accounts of Chemical Research 2008, 41, 783-792.
Momoh, P.O.; Xie, E.; Abrash, S.A.; Meot-Ner, M.; El-Shall, M.S., Gas phase reactions between acetylene radical cation and water energies, structures and formation mechanism of C2H3O+ and C2H4O+center dot ions. Journal of Physical Chemistry A 2008, 112, 6066-6073.
Glaspell, G.; Hassan, H.M.A.; Elzatahry, A.; Abdalsayed, V.; El-Shall, M.S., Nanocatalysis on supported oxides for CO oxidation. Topics in Catalysis 2008, 47, 22-31.
Fouad, O.A.; Glaspell, G.; El-Shall, M.S., Growth and characterization of ZnO, SnO2 and ZnO/SnO2 nanostructures from the vapor phase. Topics in Catalysis 2008, 47, 84-96.
Abdelsayed, V.; Glaspell, G.; Nguyen, M.; Howe, J.M.; El-Shall, M.S., Laser synthesis of bimetallic nanoalloys in the vapor and liquid phases and the magnetic properties of PdM and PtM nanoparticles (M = Fe, Co and Ni). Faraday Discussions 2008, 138, 163-180.
Ibrahim, Y.; Alsharaeh, E.; Mabrouki, R.; MomolT, P.; Xie, E.L.; El-Shall, M.S., Ion mobility of ground and excited states of laser-generated transition metal cations. Journal of Physical Chemistry A 2008, 112, 1112-1124.
El-Shobaky, G.A.; Radwan, N.R.E.; El-Shall, M.S.; Turky, A.M.; Hassan, H.M.A., The role of method of preparation of CuO-NiO system on its physicochemical surface and catalytic properties. Colloids and Surfaces A-Physicochemical And Engineering Aspects 2007, 311, 161-169.
Moussa, S.O.; El-Shall, M.S., High-temperature characterization of reactively processed nanostructure nickel aluminide intermetallics. Journal of Alloys And Compounds 2007, 440, 178-188.
Moussa, S.O.; El-Gizawy, A.S.; El-Shall, M.S., Reactive processing of nanostructured nickel aluminide intermetallics starting from elemental nanopowders. Intermetallics 2007, 15, 1057-1065.
Panda, A.B.; Glaspell, G.; El-Shall, M.S., Microwave synthesis and optical properties of uniform nanorods and nanoplates of rare earth oxides. Journal of Physical Chemistry C 2007, 111, 1861-1864.
Momoh, P.O.; El-Shall, M.S., Stepwise hydration of ionized acetylene trimer. Further evidence for the formation of benzene radical cation. Chemical Physics Letters 2007, 436, 25-29.
Mautner, M.N.; Abdelsayed, V.; El-Shall, M.S.; Thrower, J.D.; Green, S.D.; Collings, M.P.; McCoustra, M.R.S., Meteorite nanoparticles as models for interstellar grains: Synthesis and preliminary characterization. Faraday Discussions 2006, 133, 103-112.
Ibrahim, Y.; Mabrouki, R.; Meot-Ner, M.; El-Shall, M.S., Hydrogen bonding interactions of Pyridine(center dot+) with water: Stepwise solvation of distonic cations. Journal of Physical Chemistry A 2007, 111, 1006-1014.
Abdelsayed, V.; El-Shall, M.S., Vapor phase nucleation on neutral and charged nanoparticles: Condensation of supersaturated trifluoroethanol on Mg nanoparticles. Journal of Chemical Physics 2007, 126.
