Na2CO3 was chosen (rather than NaHCO3, for example) because it could be obtained at a higher purity. Equilibration with bubbling CO2 resulted in the same buffer composition. For CO2 reduction, the Na2CO3 solution was purged with CO2 at 7 sccm with the gas bubbling directly against the Au-coated Ni electrode. The headspace products were characterized using an SRI 6810-C gas chromatograph (GC) inline to the output stream of the cell. The GC was equipped with a 2 m Haysep-D column, a flame ionization detector (FID), and a thermal conductivity detector (TCD) for CO2 product detection. The glycerol oxidation products and molecular crossover were characterized using a Bruker 500 nuclear magnetic resonance (NMR) spectrometer. FEI Nova Nanolab scanning electron microscope (SEM) equipped with energydispersive X-ray spectroscopy (EDX) was used to analyze the elemental composition of deposition from the solution on the Pt-coated Ni foam cathode during seawater electrolysis. EDX was also used characterize the composition of foam electrodes before and after electrolysis to verify the presence of the electrocatalyst layer after extended electrolysis. A 3D schematic of the electrochemical cell is shown in Figure .