finds the onset potentials for Au and Ag to be -0.74 and -0.97 V vs. RHE, respectively, which aligns roughly with the values found in Figures . This possibility seems supported by literature. However, it can be difficult to determine exactly what the bidentate structure on the surface is; some authors have found bidentate peak frequencies on Ag or Au and assigned it to HCOO**, while others get similar peak frequencies and assign it to (bi)carbonate. However, we would expect (bi)carbonate to become unstable and desorb from the surface at negative potentials, making it unlikely for there to be a high coverage of it at CO 2 RR potentials.