Data set for the journal article: Tandem electrocatalytic CO2 reduction with Fe-porphyrins and Cu nanocubes enhances ethylene production

Copper-based tandem schemes have emerged as promising strategies to promote the formation<br> of multi-carbon products of the electrocatalytic CO2 reduction reaction. In such approaches,<br> the CO-generating component of the tandem catalyst increases the local concentration of CO<br> and thereby enhances the intrinsic carbon-carbon (C-C) coupling on copper. However, the<br> optimal characteristics of the CO-generating catalyst for maximizing eventual C2 production<br> are currently unknown. In this work, we developed tunable tandem catalysts comprising iron<br> porphyrin (Fe-Por), as the CO-generating component, and Cu nanocubes (Cucub) to understand<br> how the turnover frequency for CO (TOFCO) of the molecular catalysts impacts C-C coupling<br> on the Cu surface. First, we tuned the TOFCO of the Fe-Por by varying the number of orbitals<br> involved in the π-system. Then, by coupling these molecular catalysts with the Cucub, we<br> assessed the current densities and faradaic efficiencies, discovering that all of the designed Fe-<br> Por boost ethylene production. The most efficient Cucub/Fe-Por tandem catalyst was the one<br> including the Fe-Por with the highest TOFCO and exhibited a nearly 22-fold increase in the<br> ethylene selectivity and 100 mV positive shift of the onset potential with respect to the pristine<br> Cucub. These results reveal that coupling the TOFCO tunability of molecular catalysts along with<br> copper nanocatalysts opens up new possibilities towards the development of Cu-based catalysts<br> with enhanced selectivity for multi-carbon product generation at low overpotential.