Asymmetric CO–CHO Coupling over Pr Single-Atom Alloy Enables Industrial-Level Electrosynthesis of Ethylene

The electrocatalytic conversion of carbon dioxide (CO2) to ethylene (C2H4) holds great promise
for
sustainable chemical synthesis, yet achieving industrially relevant
production rates remains a significant challenge. Through computational
screening, we have identified a praseodymium (Pr) single-atom alloy
embedded in a copper (Cu) catalyst (Pr@Cu) that exhibits superior
CO2 activation and a remarkably low energy barrier for
asymmetric *CO–*CHO coupling, primarily by facilitating the
*CHO intermediate formation. Our optimized catalyst, Pr@Cu-2 (6 wt
% Pr), achieves a C2H4 Faradaic efficiency (FE)
of 64.2% at −1.6 V versus the reversible hydrogen electrode
(RHE) under a high current density of 1200 mA cm–2 in the CO2 reduction reaction (CO2RR). Furthermore,
when integrated into a 100 cm2 membrane electrode assembly
(MEA) electrolyzer, Pr@Cu-2 demonstrates robust performance, maintaining
a continuous C2H4 production rate of 21.3 mL
min–1 at 20 A for over 200 h. This work provides
fundamental insights into the role of Pr single-atom alloys in the
CO2RR and highlights their potential for scalable C2H4 electrosynthesis.