465188 Investigation of the Main Factor That Drives Selectivity on Rough Cu-Based Catalysts for CO2 Electroreduction
Recent studies2-4 have presented the importance of catalyst surface morphology and showed that rough copper (Cu) catalysts can improve selectivity and Faradaic efficiency towards hydrocarbon production. Understanding and controlling the main factor that influences selectivity on such surfaces would lead to the improvement of catalysts’ design towards the desired chemicals or fuels. This report examines the main factor that drives the selectivity on rough Cu-based catalysts surfaces. For that purpose, Cu-based catalysts were synthesized by the use of electrodeposition on copper substrates. Roughness was controlled through electrodeposition parameters of charge passed and potential applied. The evaluation of each catalyst involved the examination of surface morphology, the efficiency during the CO2 reduction, and product selectivity. Scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and capacitance measurements with cyclic voltammetry were used. The products analysis was conducted with a micro gas chromatograph (microGC) for gas products. Results showed a relation between roughness and product selectivity. Higher roughness was associated with the higher formation of ethylene (C2H4) whereas lower roughness catalysts form as main hydrocarbon product methane (CH4).
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