Investigating the role of potassium cations during electrochemical CO 2 reduction.

The specific identity of electrolyte cations has many implications in various electrochemical reactions. However, the exact mechanism by which cations affect electrochemical reactions is not agreed upon in the literature. In this report, we investigate the role of cations during the electrochemical reduction of CO 2 by chelating the cations with cryptands, to change the interaction of the cations with the components of the electric double layer. As previously reported we do see the apparent suppression of CO 2 reduction in the absence of cations. However, using in situ -SEIRAS we see that CO 2 reduction does indeed take place albeit at very reduced scales. We also observe that cations play a role in tuning the absorption strengths of not only CO 2 as has been speculated, but also that of reaction products such as CO.