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> ABRC Home > People List > Daniel Strongin
FACULTY > Daniel Strongin
 Research Interests
The Strongin (in collaboration with Schoonen) laboratory is focused is investigating the surface reactivity of pyrite, FeS2, and pyrrhotite, FeS, in the hydrothermal environment with in situ vibrational spectroscopy. A key hypothesis for this particular project is whether FeS-like defects on pyrite or pyrrhotite can promote biologically relevant chemistry. Furthermore, are the active centers of enzymes related to defect structures on minerals such as pyrite rather than to the structural motif of the ideal mineral structure? This research will be carried out in close collaboration with Robert Szilagyi who can help guide us on how to best modify our inorganic mineral catalysts in view of the structural details of enzyme active sites. These possibilities are being investigated in the current study in view of the pyrite pulled reaction, which can be written as FeS + H2S → FeS2 + H2. The conversion of FeS to FeS2 in the presence of H2S at hydrothermal vents has been hypothesized to provide the energy necessary for prebiotic chemistry.
To date, the experimental apparatus to study the relevant reactions has been assembled and preliminary results have recently been obtained. The reaction/infrared cell is capable of achieving pressures close to 400 bar and temperatures up to 300ºC. Studies are currently focused on the synthesis of ammonia under hydrothermal conditions. In terms of the pyrite-pulled reaction, ammonia production is hypothesized to result from the oxidation of FeS (i.e., FeS + H2S ® FeS2 + 2H+ + 2e-) coupled with the reduction of dinitrogen (N2 + 8H++ 6e- → 2NH4+). Recent experiments have involved investigating the reaction of dissolved nitrogen in H2S- bearing solutions with FeS and/or FeS2 at 120 ºC and 100 bar. Both bulk and nanocrystalline forms of FeS are being used in these experiments. Furthermore, stoichiometric defects can be controllably introduced into the mineral and the effect of these structural alterations on ammonia production will be investigated. Additional work will investigate the decomposition fragments that result from the reaction of FeS in an ammonium containing solution (i.e., the back reaction).
Selected Publications
(1) “Abiotic ammonium formation in the presence of Ni-Fe metals and alloys and its implications for the Hadean nitrogen cycle,” Smirnov A, Hausner D, Laffers R, Strongin DR, Schoonen MAA., Geochemical Transactions (2008) 9, 1.
(2) “Similarities in 2-and 6-line ferrihydrite based on pair distribution function analysis of X-ray total scattering.” Michel, F. M., Ehm, L., Liu, G., Han, W.Q., Strongin, D.R., Antao, S.M., Chupas, P.J., Lee, P.L., Knorr, K., Eulert, H., Kim, J., Grey, C.P., Celestian, A.J., Gillow, J., Schoonen, M.A.A., Parise, J.B., Chemistry of Materials (2007) 19 (6), 1489-1496.
(3) “The structure of ferrihydrite, a nanocrystalline material.Michel,” F. M., Ehm, L., Antao, S.M., Lee, P.L., Strongin, D.R., Chupas, P.J., Liu, G., Schoonen, M.A.A., Phillips, B.L., Parise, J.B., Science (2007) 316 (5832), 1726-1729.
(4) "Physical Structures of Lipid Layers on Pyrite," Xiang V. Zhang, Treavor A. Kendall, Jun Hao, Daniel R. Strongin, Martin A. A. Schoonen, and Scot T. Martin, Environmental Science and Technology, (2006) 40, 1511-1515.
(5) "Characterization and surface reactivity of ferrihydrite nanoparticles assembled in ferritin," Liu, G.; Debnath, S.; Paul, K.W.; Han, W.; Hausner, D.B.; Hosein, H.-A.; Michel, F.M.; Parise, J.B.; Sparks, D.L.; Strongin, D.R., Langmuir (2006), 22(22), 9313-932.
(6) "Pyrite-induced hydroxyl radical formation and its effect on nucleic acids," Cohn, C.A.; Mueller, S.; Wimmer, E.; Leifer, N.; Greenbaum, S.; Strongin, D.R.; Schoonen, M.A.A., Geochemical Transactions (2005) 7, 1-11.
(7) "Electronic structure of nanoscale iron oxide particles measured by scanning tunneling and photoelectron spectroscopies," Preisinger, M.; Krispin, M.; Rudolf, T.; Horn, S.; Strongin, D. R. Physical Review B. (2005), 71, 165409.
(8) "Environmental Catalysis," Schoonen, M.A.A.; Strongin, D.R. Electron Transfer at Mineral Surfaces., Ed. V. H. Grassian, CRC Publishing, Boca Raton, FL, 2005.
(9) "Mechanistic aspects of pyrite oxidation in an oxidizing Gaseous environment: an in situ HATR-IR isotope study," Usher, C.R.; Paul, K.W.; Narayansamy, J.; Kubicki, J.D.; Sparks, D.L.; Schoonen, M.A.A.; Strongin, D.R., Environmental Science and Technology, (2005) 39, 7576-7584.
(10) "Origin of Oxygen in Sulfate during Pyrite Oxidation with Water and Dissolved Oxygen: An In Situ Horizontal Attenuated Total Reflectance Infrared Spectroscopy Isotope Study," Usher, Courtney R.; Cleveland, Curtis A., Jr.; Strongin, Daniel R.; Schoonen, Martin A. Environmental Science and Technology (2004), 38(21), 5604-5606
Lab Personnel
Soujanya Singi Reddy
Graduate Student
Soujanya@temple.edu
Riley Murphy
Graduate Student
riley.murphy@temple.edu
Alex Gordon
Graduate Student
alex.gordon@temple.edu
Collaborators (outside the ABRC)
Professor Donald Sparks
(reactivity of manganese oxyhydroxide surfaces)
Department of Soil Science
University of Delaware
Professor Jim Kubicki (computational Chemistry)
Department of Geosciences
Penn State University
Professor Clare Grey (reactivity of iron oxyhydroxide surfaces)
Department of Chemistry
Stony Brook University
Professor Richard Reeder
(reactivity of iron oxyhydroxide surfaces)
Department of Geosciences
Stony Brook University
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