Catalysis Science & Engineering, Poster
CE-129

Enhanced electrochemical reduction of CO2 over Cu-based catalysts modified with p-block elements

G. O. Larrazábal1, T. Shinagawa1, A. J. Martín1, J. Pérez-Ramírez1*
1ETH Zurich

The coupling of electrosynthesis technologies with renewable energy sources can potentially turn CO2 emissions into a valuable feedstock for the production of fuels and chemicals while contributing to closing the anthropogenic carbon cycle.1,2 Copper foil electrodes prepared from the reduction of thick oxide films (OD Cu) effectively target the reduction of CO2 to CO at moderate overpotentials.3 However, such electrodes display modest current densities, and their preparation on bulk metallic substrates makes them unsuitable for practical applications. In this context, we have recently shown that Cu2O nanocatalysts prepared by a simple and potentially scalable solvothermal route are more active and selective for CO evolution than OD Cu electrodes under similar conditions.4 Additionally, the performance of these catalysts can easily be enhanced by introducing Sn and In into the Cu2O matrix through the addition of the corresponding precursors to the synthesis medium (Figure 1). Based on this insight, we extend this methodology to evaluate the catalytic effect of introducing most non-hazardous p-block elements as modifiers, revealing a powerful strategy to tune the selectivity toward other eCO2RR products while maintaining a high selectivity at reduced overpotentials.

Figure 1 Current efficiency (bars), total current density (circles) and partial current density for CO (diamonds) in CO2 electroreduction over unmodified (Cu2O-ud) and Sn- and In-modified Cu2O electrocatalysts prepared by a simple and potentially scalable solvothermal synthesis (potential indicated versus RHE in CO2-saturated 0.1 M KHCO3). The number in the codes indicates the Cu:Sn or Cu:In ratio of the catalyst.

[1] E. V. Kondratenko, G. Mul, J. Baltrusaitis, G. O. Larrazábal, J. Pérez-Ramírez, Energy Environ. Sci. 2013, 6, 3112.
[2] A. J. Martín, G. O. Larrazábal, J. Pérez-Ramírez, Green Chem. 2015, 17, 5114.
[3] C. W. Li, M.W. Kanan, J. Am. Chem. Soc. 2012, 134, 7231.
[4] G. O. Larrazábal, A. J. Martín, F. Krumeich, R. Hauert, J. Pérez-Ramírez, ChemSusChem 2017, 10, 1255.