Synthesis of Composition-Tunable Syngas from Efficiently Electrochemical Conversion of CO2 over AuCu/CNT Bimetallic Catalyst

Syngas is significant for the chemical industry for the synthesis of a variety of hydrocarbon fuels and chemicals. Different syngas-based products require syngas with different CO/H2 ratios, which depend mainly on the design of the catalyst. Under this background, we successfully synthesized syngas by electroreduction of carbon dioxide (CO2) with a controllable CO/H2 ratio over a AuCu bimetallic catalyst. In contrast to the monometallic Au and Cu catalysts, the AuCu bimetallic catalyst gives a 95.2% of Faradaic efficiency (FE) at only 290 mV on the selective conversion from CO2 to CO. By tuning the Cu/Au ratio and potential during the electrochemical conversion, the H2/CO in the obtained syngas products can be obtained at the wide range of 0.12 to 5.24. We propose that the controllable H2/CO ratio from CO2 is significant in industrial production and will decrease the cost of catalyst fabrication.