The electroreduction of carbon dioxide (CO2) to high-energy-density C3 products (e.g., n-propanol (n-PrOH)) is of great importance but restricted by low selectivity and activity. Herein, we developed a novel CuO/SiO2 electrocatalyst, with multi-layered CuO as the core and an SiO2 layer as the shell, for improving CO2-to-n-propanol conversion efficiency. Such a unique structure could stabilize and confine C1 and C2 intermediates, favoring their contact and carbon trimerization towards n-propanol formation. It delivered an n-propanol Faraday efficiency of 13.3% at −1.65 V with a partial current density of 94.0 mA cm−2 in a flow cell. The mechanism for electrocatalytic CO2-to-n-PrOH conversion over the CuO/SiO2 catalyst was investigated using in situ Raman spectroscopy and in situ attenuated total reflection surface-enhanced infrared absorption spectroscopy.
