1William C. Tucker, 1Abrar H. Quadery, 1Alfons Schulte, 1,3,4Richard G. Blair, 1William E. Kaden, 1,2Patrick K. Schelling, 1Daniel T. Britt
Icarus (in Press) Link to Article [https://doi.org/10.1016/j.icarus.2017.08.027]
1Department of Physics, University of Central Florida, Orlando, FL 32816-2385, USA
2Advanced Materials Processing and Analysis Center, University of Central Florida, Orlando, FL 32804, USA
3Cluster for the Rational Design of Catalysts for Energy Applications and Propulsion, University of Central Florida, Orlando, FL 32816, USA
4Center for Advanced Turbomachinery and Energy Research, University of Central Florida, Orlando, FL 32816, USA
It is demonstrated that olivine powders heated to subsolidus temperatures in reducing conditions can develop significant concentrations of 10-50 nm diameter Fe nanoparticles on grain surfaces and that these display strong catalytic activity not observed in powders without Fe nanoparticles. Reduced surfaces were exposed to NH3, CO, and H2, volatiles that may be present on the surfaces of comet and volatile-rich asteroids. In the case of NH3 exposure, rapid decomposition was observed. When exposed to a mixture of CO and H2, significant coking of the mineral surfaces occurred. Analysis of the mineral grains after reaction indicated primarily the presence of graphene or graphitic carbon. The results demonstrate that strong chemical activity can be expected at powders that contain nanophase Fe particles. This suggests space-weathered mineral surfaces may play an important role in the synthesis and processing of organic species. This processing may be part of the weathering processes of volatile-rich but atmosphereless solar-system bodies.