Yang Rong PhD defense

Présentation

**Solid State Chemistry and Materials (**CSM) team

**Abstract** Natural and anthropogenic organic compounds undergo a range of interfacial processes that control their transformation, stabilization, and mobility in the environment. This thesis investigates how mineral-water, air-water and ice-confined interfaces regulate the fate of phenolic compounds and PFAS. Freeze-thaw conditions strongly promote catechol transformation in the resence of birnessite or Fe(III) by concentrating reactants within confined liquid microenvironments and enhancing oxidation, molecular coupling, and transfer of organic carbon to the solid phase. In unsaturated porous media, PFOA and PFOS transport is controlled by adsorption at solid-water and air- water interfaces,.together with solution chemistry and hydrodynamic onditions. Finally, water films formed on TiO2 surfaces under elevated relative humidity promote the O2-dependent transformation of 6:2 FTAB, accompanied by C–F bond cleavage and the formation of shorter-chain fluorinated products. Together, these results show that environmental interfaces act as reactive domains that regulate both organic carbon transformation and the retention, transport, and degradation of persistent contaminants.

**Jury** Dominik J. WEISS, Professor, Imperial College London, United Kingdom / President Johannes LÜTZENKIRCHEN, Scientist, Karlsruhe Institute of Technology (KIT), Germany / Examiner Dominik HEGER, Professor, Masaryk University, Czech Republic / Reviewer Jurate KUMPIENE, Professor, Luleå University of Technology, Sweden / Reviewer **Supervisors** Khalil HANNA, Professor, University of Rennes, ENSCR, ISCR / PhD Director Jean-François BOILY, Professor, Umeå University, Sweden / PhD Co-Director

**Contacts** Yang Rong, yang.rong@ensc-rennes.fr Khalil Hanna, khalil.hanna@ensc-rennes.fr