The main objective of this research is to integrate electrochemical and microscopic approaches to understand reaction mechanisms and pathways of the uranyl reduction and nucleation mediated by magnetite and ilmenite. and This experimental data reveal how natural iron minerals mediate redox reactions of redox sensitive elements. We measure electrochemical responses of dissolved uranyl ions (UO22+) to potentials in the presence of organic molecules. The atomic force microscopic (AFM) images show nucleation of reduced uranyl on ilmenite (FeTiO3) as a function of potential.
Kim, Y., Marcano, M. C., Kim, S., & Becker, U. (2021). Reduction of uranyl and uranyl-organic complexes mediated by magnetite and ilmenite: A combined electrochemical AFM and DFT study. Geochimica et Cosmochimica Acta, 293, 127–141. https://doi.org/10.1016/j.gca.2020.10.016 and Walker S. M., Marcano M. C., Bender W. M. and Becker U. (2016) Imaging the reduction of chromium (VI) on magnetite surfaces using in situ electrochemical AFM. Chemical Geology 429, 60-74.
Files are uploaded as crystallographic information files (.cif), the standard text file format for representing crystallographic information.
These files contain the optimized molecular models for pentavalent plutonium incorporation reactions into/onto barite, anglesite, celestine, anhydrite, aragonite, and calcite host minerals.
Gebarski, B. B. and Becker, U. Quantum-Mechanical Determination of the Incorporation of Pentavalent Plutonium into Carbonate and Sulfate Minerals. (2019) Geochimica et Cosmochimica Acta. https://doi.org/10.1016/j.gca.2019.10.015