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> ABRC Home > People List > Martin A.A. Schoonen
FACULTY > Martin A.A. Schoonen
Martin A.A. Schoonen, Associate Director of the ABRC
Research Interests
Research in the Schoonen’ group is focused on the role mineral surfaces may have played in prebiotic chemistry. The emphasis is on understanding the role of mineral surfaces and their defects in the transformation of dinitrogen into ammonia.
Reduced nitrogen in the form of ammonia or ammonium is thought to be a key reactant in prebiotic synthesis on the Hadean Earth. Atmospheric models assuming a sufficiently reducing environment to stabilize ammonia have fallen out of favor. Instead the Hadean atmosphere is thought to be moderately reducing, with dinitrogen as the stable form of nitrogen. Without free reduced ammonia in the atmosphere, ammonia or ammonium have to either be delivered to the Earth from space or formed by reducing dinitrogen. Recent research in Schoonen’s group has focused on the possible delivery of reduced nitrogen by meteorites as well as the reduction of dinitrogen under a variety of conditions in the presence of iron sulfides, metals, and metal alloys. Much of this work is conducted in collaboration with the Strongin group.
Our research methods rely heavily on the ability to synthesize metal sulfides with high specific surface under strictly anoxic conditions. Typically hydrothermal synthesis routes are used to achieve this. Structural characterization of nano-size to micron-size particles is done in collaboration with the Parise group and often involves advanced synchrotron-based techniques. The formation of ammonia is studied in situ over a range of pressure and temperature conditions. Flow Injection Analysis coupled with a titanium hydrothermal reaction cell is used to study ammonia formation at temperatures up to 200ºC. Reduction of dintrogen with hydrogen sulfide in the presence of FeS is being studied using Attenuated Total Reflection FTIR. This work is spearheaded by the Strongin group.
The experimental work in the Schoonen group is complemented by theoretical studies that explore the weathering of Earth’s primordial crust. The goal of this work is to determine the stability of weathering products, such as nickel alloys, on the Hadean Earth and the redox state of the oceans and atmosphere.
Selected Publications
Smirnov A., Hausner D., Laffers R., Strongin D. R., Schoonen, M. A. (2008): Abiotic ammonium formation in the presence of Ni-Fe metals and alloys and its implications for the Hadean nitrogen cycle. Geochemical Transactions, 9:5.
Zhang X. V., Ellery S. P., Friend C. M., Holland H. D., Michel F. M., Schoonen M. A. A., Martin S. T. (2007): Photodriven reduction and oxidation reactions on colloidal semiconductor particles: Implications for prebiotic synthesis. Journal of Photochemistry and Photobiology A: Chemistry 185, 301-311.
Michel, F.M., Antao, S.M., Chupas, P.J., Lee, P.L., Parise, J.B., and Schoonen, M.A.A. (2005): Short- to medium-range atomic order and crystallite size of the initial FeS precipitate from pair distribution function analysis. Chem. Mater. 2005, 17, 6246-6255.
Schoonen M., Smirnov A., Cohn C. (2004): A Perspective on the Role of Minerals in Prebiotic Synthesis. Ambio, 33, 8, 539-551.
Schoonen M. A. A., Xu Y. (2001): Nitrogen Reduction Under Hydrothermal Vent Conditions: Implications for the Prebiotic Synthesis of C-H-O-N Compounds. Astrobiology, 1, 2, 133-142.
Lab Personnel
Alexander Smirnov
Post-doctoral Associate
Alexander.Smirnov@stonybrook.edu
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