Researchers develop graphene/silicon carbide catalyst for selective CO2 to ethanol conversion

A research team, led by Profs. Chen Wei and Wei Wei from the Shanghai Advanced Research Institute (SARI) of the Chinese Academy of Sciences, has developed a novel graphene/silicon carbide (SiC) catalyst for efficient CO₂ photoelectroreduction to ethanol (C₂H₅OH).

Using sunlight to produce valuable chemicals and fuels from carbon dioxide (CO₂), i.e., artificial photosynthesis (AP), is a promising strategy to achieve solar energy storage and a negative carbon cycle. However, selective synthesis of C₂ compounds with a high CO₂ conversion rate remains challenging for current AP technologies. The composite catalyst in this work, which comprises SiC substrate, interfacial layer (IL), and few-layer graphene overlayer, can help to achieve the precise control of active intermediates for C-C coupling.

The team performed CO₂ photoelectroreduction over a graphene/silicon carbide (SiC) catalyst under simulated solar irradiation with ethanol (C₂H₅OH) selectivity of>99 % and a CO₂ conversion rate of up to 17.1 mmol g_cat−1 h−1 with sustained performance. 

Experimental and theoretical investigations indicated an optimal interfacial layer to facilitate the transfer of photogenerated electrons from the SiC substrate to the few-layer graphene overlayer, which also favored an efficient CO₂ to C₂H₅OH conversion pathway.