We utilized infrared spectroscopy to detect potential reaction intermediates en route to CH4 production to derive a mechanistic explanation for the observed selectivity of Co Terpy-RF. Using the system at open circuit conditions as a background, we noted bands at 1650 and 2640 cm -1 under CO2R conditions (Fig. ). These bands match C=O and C-H vibrational modes and their presence indicates a buildup of CHxOy species that are produced downstream of the CO intermediate. The CO intermediate was not seen. This may point to the reduction of adsorbed CO2 and CO, established species en route to CH4 production, 38 as being relatively facile compared to the final steps in the reaction process such as C-O cleavage or C/O hydrogenation. This is also supported by the lack of significant CO produced from this system. Since CO2R to CH4 is an 8 e - /8 H + process, there must be a route for proton transfer to the catalytic sites within the hydrophobic assembly and we began to suspect that there was another mechanism of H + transfer beyond the simple diffusion of water molecules.