Dissolution of iron(hydr)oxides is a key process in the biogeochemical cycle of iron (Fe) and biological Fe acquisition. My doctoral research examines synergistic effects of redox processes and ligand-controlled dissolution of Fe(III)(hydr)oxide phases. I am mainly investigating the catalytic effect of Fe(II) on ligand-controlled dissolution and the fate of Fe(II) before and during dissolution. For this purpose, I am using combinations of batch experiments, isotopes and FTIR-spectroscopic measurements.
Traces of Fe(II) in oxic environments and at redox interfaces could be formed by reducing ligands, by light, and by iron-reducing microorganisms. Fe(II)-catalyzed ligand-controlled dissolution with formation of dissolved Fe(III) complexes is thus likely important in many natural systems such as in soils, at oxic-anoxic interfaces in shallow lakes and ponds, in groundwater, and generally in environments subject to dynamic redox conditions.
The project is being carried out in collaboration with the group of Prof. Stephan Kraemer, Department of Environmental Geosciences, University of Vienna and was funded by Swiss National Science Foundation.