The reversible AQ redox reaction occurs at 𝐸 1 𝑜′ formal potential with an electrochemical rate constant of 𝑘 0 . The chemical quinone-adduct formation reaction occurs at a chemical rate constant of 𝑘 𝑐 , which would result in AQ(CO2)2 2-species with a redox reaction occurring at 𝐸 2 𝑜′ formal potential and with 𝑘′ 0 electrochemical rate constant. It is important to note that the AQ redox reaction (reaction ) unfolds in two single electron steps, as detailed in the SI Section 2.3. However, these two steps occur with less than 30 mV separation (see Section 2.3 and Figure ), leading to a single merged peak in the cyclic voltammogram profile, and thus, the assumption is made that reaction proceeds in one two-electron step. Similarly, reaction may occur in two sequential steps but based on the shape of the merged peaks in the CV profile, these sequential steps must occur with small potential separations. The nearly identical location of the reduction peak under both N2 and CO2 environments suggests that the sequential reduction of AQ is unaffected by CO2 complexation. Considering these observations, we proceeded with fitting the CV profiles to the ECE scheme, with details provided in SI Section 2.4. Examples of a fitting for 1,8-BTMAPAQ are shown in Figure , and the rest of the fittings are provided in Figures , indicating a very good agreement between the model and the experimental data. It is important to note that the properties of the AQ redox reaction (reaction ( )), such as its electrochemical reaction rate constant and diffusion coefficient can be extracted in isolation under nitrogen environment. Figures show the properties extracted from rotating disk electrode tests under a nitrogen environment for all the isomers. The fitting parameters achieved for AQ under CO2 are close to the range of the extracted properties of AQ in isolation under a nitrogen environment. For 1,4-and 1,5-BTMAPAQ isomers, an increase in scan rate barely results in current extraction at the potential relevant to AQ reduction. Therefore, we report a lower limit on 𝑘 𝑐 for these two isomers, below which the chemical reaction would be too slow to keep up with the fast scan rates. However, for 1,8-BTMAPAQ, an exact value of 𝑘 𝑐 , rather than a limit, is reported.