1.3. Electron transfer and reaction intermediates mediated by imidazolium cations From a mechanistic perspective, the initiation of CO2 reduction has been argued to involve a first electron transfer to the CO2 molecule 19, 38. In the case of a metal electrode catalyst, this step follows CO2 adsorption. The following central equation can be considered for CO2 activation: [Eq 1.1] Due to the high reactivity and short lifespan of this intermediate, as identified by Bard et al.39 , the predominant reaction and subsequent product distribution considerably depend on the nature of the electrode material40, the surrounding microenvironment41-42, and the availability of protons43. In situations involving low-proton aprotic media, numerous studies have documented the formation of CO, oxalate, and carbonate as the primary products. Additionally, in the presence of residual water, other products like hydrogen, glyoxalate, glycolic acid, glyoxylic acid, and formic acid have been observed in the reaction mixture44-48. The formation of CO in non-aqueous media has predominantly been linked to a disproportionation reaction. In this process, upon the second electron transfer to an adsorbed *CO2 intermediate, carbonate and CO are simultaneously generated in equimolar proportions. Oxalate, on the other hand, has been proposed to emerge from a self-coupling reaction of adsorbed *CO2 intermediates, while the presence of water has been suggested to drive the formation of formate 31, 36.The first reaction stage mentioned in Eq. [1.1] requires a significantly negative standard potential, as reported to be -2.21 V vs. SCE on a mercury electrode in DMF solvent44. Recent work by Koper et al. 49 has even demonstrated the absence of CO2 conversion in the absence of solvation effects that stabilize the negatively charged CO2 intermediate. Without water as a potential
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