Introduction In the preceding chapters, we explored the fundamental mechanisms underlying the substantial enhancement in performance of Au electrodes in non-aqueous CO2 reduction through the utilization of the 1,3-dimethyl imidazolium cation. Building upon these findings, Chapter 7 seeks to broaden our comprehension by investigating two crucial aspects: a) the impact of alkyl chain length within the imidazolium cation, and b) the influence of the nature of alkali metal cations on the non-aqueous CO2 reduction process. It is worth noting that a comprehensive analysis of these electrolyte effects necessitates dedicated molecular dynamics calculations in conjunction with experimental investigations. However, such computational support lies beyond the scope of this chapter, as our objective here is to establish the foundation for future studies in non-aqueous media. Results and Discussion Figure 7.1 a presents the cyclic voltammetry results for three imidazolium cations: 1,3dimethyl imidazolium NTf2 (MM), 1-methyl-3-heptyl imidazolium NTf2 (HM), and 1-methyl3-nonyl imidazolium NTf2 (NM), as co-catalysts for CO2 reduction on an Au electrode in anhydrous acetonitrile. It is evident that an increase in the alkyl chain length leads to a decrease in the activity for CO2 reduction, especially evident by the high onset potential for the NM imidazolium. In Figure 7.1 b, we present the optimized structures of the cations obtained through DFT calculations, along with VDD charge analysis specifically focusing on the C2-H2 bonds. Interestingly, the VDD charge analysis reveals no significant differences in the positive charge densities for the C2 and H2 atoms of the imidazolium rings. Thus, it is unlikely that the variations in charge densities or proton donation from the H2 atoms play a significant role in the observed differences in activities. Instead, we propose that the bulkiness of the cations,
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