(478g) Hybrid Organic-Inorganic Interfaces Drive CO2 Reduction to C2 hydrocarbons | AIChE

(478g) Hybrid Organic-Inorganic Interfaces Drive CO2 Reduction to C2 hydrocarbons


Che, F., University of Massachusetts Lowell
Gu, Z., University of Massachusetts Lowell
To mitigate the excess atmospheric CO2 sustainably, one promising way is CO2 electroreduction reaction into valuable C2 products (CO2RR-to-C2) such as ethanol and ethylene using renewable electricity.1 Cu is considered to be the most ideal pure metal catalyst for CO2RR-to-C2 but suffers from high overpotentials and low selectivity of C2 species.

To reduce the overpotentials and enhance the selectivity of CO2RR-to-C2 over Cu, we designed a hybrid organic-inorganic interface between aminothiolate self-assembled monolayer (SAM) and Cu catalyst.2 In particular, we studied the electrocatalytic performance of CO2RR-to-C2 via varying the carbon chain lengths and configurations of aminothiolate SAMs (Figure 1a). Our results show that: (1) aminothilate SAMs prefers lying-down over the Cu surface at a low coverage (1/16 and 2/16 monolayer (ML)), while it favors standing-up over the surface at a high coverage (4/16, 8/16 ML) due to the lateral interactions; (2) under the electroreduction condition (pH = 13, USHE = -1.0 V), aminothiolates at 8/16 ML are unstable and prone to be reduced to thiols and desorb into solution (Figure 1b); (3) the aminothiolate SAM with longer carbon chain lengths is more stable (Figure 1b); and (4) a low coverage of SAM with lying-down structure creates hybrid organic-inorganic active sites for stabilizing C2 intermediate, while a high coverage of SAM with standing-up structure induces confinement space effect for enlarging the adsorption energy difference of CO* and COH*. Both lying-down and standing-up aminothiolate SAMs decrease the activation barriers and reaction energies of C-C coupling (rate-limiting step of CO2RR-to-C2 over Cu) (Figure 1c). Overall, this study leads to a new type of electrocatalysts – hybrid organic-inorganic interfaces.


1. Li, J.; Ozden, A.; Wan, M. et al., Nat. Commun. 2021, 12 (1), 2808.

2. Wan, M.; Gu, Z.; Che, F., ChemCatChem 2021, 14 (4), e202101224.