Abstract
To date, the understanding of various modes of CO(2) mass transport remains incomplete, impeding the transfer of catalysts identified in the more accessible electrochemical batch cells to high-performance flow cells. In this work, we demonstrate that the meniscus region formed between the electrode and the convex liquid level due to the electrowetting of the catalyst plays a vital role in the CO(2)RR in batch cells. CO(2)RR in the meniscus region in batch cells exhibits similar performance with that in flow cells, and the performance disparity between these two configurations largely disappears when conducting CO(2)RR primarily in the meniscus region. An assembled double-sided gas diffusion electrode with a gas channel is developed to maximize the meniscus-like region, achieving a CO(2)RR partial current density of 640 mA/cm(2)(geo) on commercial Cu in the KHCO(3) electrolyte. This performance represents the highest CO(2)RR activity in neutral buffered media.