Exploring the influence of cell configurations on Cu catalyst reconstruction during CO electroreduction.

Membrane electrode assembly (MEA) cells incorporating Cu catalysts are effective for generating C chemicals via the CO reduction reaction (CORR). However, the impact of MEA configuration on the inevitable reconstruction of Cu catalysts during CORR remains underexplored, despite its considerable potential to affect CORR efficacy. Herein, we demonstrate that MEA cells prompt a unique reconstruction of Cu, in contrast to H-type cells, which subsequently influences CORR outcomes. Utilizing three Cu-based catalysts, specifically engineered with different nanostructures, we identify contrasting selectivity trends in the production of C chemicals between H-type and MEA cells. Operando X-ray absorption spectroscopy, alongside ex-situ analyses in both cell types, indicates that MEA cells facilitate the reduction of CuO, resulting in altered Cu surfaces compared to those in H-type cells. Time-resolved CORR studies, supported by Operando analysis, further highlight that significant Cu reconstruction within MEA cells is a primary factor leading to the deactivation of CORR into C chemicals.