Multi-layered CuO/SiO2 core–shell structure improves electrocatalytic CO2-to-n-propanol conversion

Abstract

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.