Under these conditions however, we observed CH4 as the dominant product. Its production increased until -0.99 V vs. RHE, after which point the excessively negative potentials resulted in catalyst degradation (Fig. ). Quantifying the selectivity (FE) for all products observed, we noted that CH4 production accounts for up to 60% of the total electron flow through the cathode at -0.79 V vs. RHE (Fig. ). Finally, we measured the stability of the system through an extended electrolysis at -0.79 V vs. RHE and recorded an overall FE for CH4 of 71%. Based on the quantity of redox-active Co Terpy-RF on the electrode, the turnover number for CH4 production (TONCH4) was >18,000. After this measurement, the electrode still exhibited the same spectroscopic signature as prior to electrolysis and a similar visual appearance, pointing to a high stability of Co Terpy-RF under these parameters (Fig. ). The tendency to produce CH4 was intriguing as Co polypyridine catalysts were only noted to produce formate or CO in previous studies, including in our own test of homogeneous Co Terpy-RF in CH3CN. In fact, electrocatalytic CH4 production by any molecular catalyst is rare. We first compared several analogous Co terpyridine catalysts in our GDE setup (Fig. ). Co Terpy-OH on the GDE surface only produced CO at less than 1% FE. Co Terpy-R (R=decyl, C10H21) with non-fluorinated alkyl chains, on the other hand, did give a noticeable amount of CH4 at approx. 10% FE, however still far below the FE seen with Co Terpy-RF. This system would likely also feature Co Terpy units within a hydrophobic pocket and similar redox behaviour (Fig. ), but without the high degree of ordering driven by the strong perfluoro-perfluoro interactions in the Co Terpy-RF system. This indicated that both a hydrophobic environment and ordered molecular assembly are important for CH4 production. Interestingly, using an equivalent amount of CoCl2 also gave small amounts of CH4. Other controls such as carrying out the reaction in the absence of Co Terpy-RF or CO2 did not give measurable CH4 production.