CO2 electrolyzers have gained significant attention as a viable technology to convert CO2 to multi-carbon products, thus helping mitigate carbon emissions and promote carbon circularity. To be competitive with current chemicals manufacturing, the selectivity of multi-carbon products and the process energy efficiency in CO2 electrolyzers needs yet to be improved. This work aims to address these challenges and make this reaction more sustainable by enhancing ethylene selectivity and improving reactor energy efficiency. To achieve this, we couple product analysis with surface enhanced infrared adsorption spectroscopy (SEIRAS) and Raman spectroscopy (SERS) to analyze reaction performance and investigate the effect of different reaction parameters (such as temperature) on intermediate conversion and product formation.