A research team led by Professors CHEN Wei and Professor WEI Wei of the Shanghai Advanced Research Institute (SARI) of the Chinese Academy of Sciences has developed novel graphene/silicon carbide (SiC) catalysts for efficient photoelectroreduction CO2 to ethanol (C2H5OH). .
Composed of a SiC substrate, an interfacial layer (IL) and a few-layered graphene overlayer, the composite catalyst can help achieve precise control of active intermediates for DC coupling.
An optimal structure of IL allows the photogenerated electrons from the SiC substrate to be easily transferred to the active sites of the graphene layer. The reaction intermediates can then be efficiently formed and stabilized due to their strong adsorption on the active sites and the high electron density of the graphene surface.
The researchers found that CH3OH formation was largely suppressed in favor of DC coupling. Thus, C2H5OH was exclusively generated with >99% selectivity and a CO2 conversion rate of 17.1mmol gcat-1h-1 under simulated solar irradiation with little bias (-50 mV bias vs Ag/AgCl) and environmental conditions.
Thus, the photoelectrocatalytic performance of the optimal catalyst in the production of C2 products from CO2 was at least two orders of magnitude higher than that of the latest generation AP catalysts.
The results have been published in Angewandte Chemie International Edition.
The references: Feng, G., Wang, S., Li, S., Ge, R., Feng, X., Zhang, J., Song, Y., Dong, X., Zhang, J., Zeng, G., Zhang, Q., Ma, G., Chuang, Y.-D., Zhang, X., Guo, J., Sun, Y., Wei, W., Chen, W. (2023) “Highly selective photoelectroreduction of Carbon Dioxide to Ethanol on Graphene/Silicon Carbide Composites » Angew. Chem. Int. Ed. doi: 10.1002/anie.202218664