Simulations of CO2 reduction in molecular materials

The anthropogenic effect induces, among other gases, an increase of atmo- spheric carbon dioxide concentration, which contributes to global warming and the resulting climate change. Compared to the pre-industrial era, a tem- perature increase of 1.5 °C was recorded in 2024. Although this may seem like a modest amount, it represents a significant accumulation of heat. One way to counteract this increase is by using catalysts towards the conversion of CO2 to high-value products. This Ph.D. thesis focuses on the development and mechanistic investigation of promising catalysts capable of reducing CO2 to HCOOH or CO, two important chemical feedstocks. The first study shows that by using the Mn(bpy)(CO)3 Br catalyst along with triethylamine and isopropanol as additives, the electrochemical reduction of CO2 is shifted from CO to HCOOH. The reaction mechanism was elucidated, highlighting the critical role of these additives. Subsequently, in the second study, changes were made to the bipyridine ligand of the Mn(bpy)(CO)3Br catalyst to see how it would affect catalyst performance and selectivity. We compared two Mn catalysts with two and four pendant amine groups and performed density functional theory calculations to investigate the effect of these pendant groups. Besides transition metal-based molecular catalysts, this thesis also covers the modeling of metal-organic frameworks. To gain deeper insights into their catalytic properties, in the third study we first developed a new cationic dummy atom model that successfully reproduced experimental values and ensured successful and stable molecular dynamics simulations. Beyond that, some properties such as the "breathing phenomena" were modeled. Newly parame- trized force fields for metal ions showed to be transferable in our fourth project, where cobalt-based MOF, Al2(OH)2TCPP-Co, was investigated due to its po- tential for reducing CO2 to CO in an aqueous electrolyte. Simulations pro- vided insights into the spatial distribution of CO2 and counter ions, which further led to conclusions that can help further research within the field on how to enhance MOF structure for electrochemical conversion. This work provides the reader with knowledge about interesting candi- dates for electrochemical CO2 conversion and ideas for possible advancements in the future within the field. Additional literature, that exceeds the scope of this research, will be included to provide a broader overview of the problem and potential solutions to it.