Dimensionality–Driven Electronic Modulation at Metal–Perovskite Interfaces for Electrochemical CO 2 Reduction
Seunghyun Chun, Hakhyeon Song, Myeongbum Ko, Yeneul Lim, Dongho Heo, Jae Won Shin, Hyunsik Kim, Hyeyoung Shin, Hyosun LeeABSTRACT
Electrochemical CO 2 reduction reaction (CO 2 RR) offers a sustainable approach for converting CO 2 into value–added chemicals; however, its practical implementation remains limited by high overpotentials and poor selectivity. Metal–oxide interface engineering has recently emerged as a promising strategy to overcome these limitations. While the modulation of metal–support interactions is well established in gas–phase catalysis, their mechanistic manifestation within electrochemical interfaces remains insufficiently understood. Specifically, the influence of support dimensionality on the local CO 2 RR microenvironment has not been addressed. In this study, we systematically investigate the role of support dimensionality by comparing Au nanoparticles (NPs) supported on two‐dimensional (2D) Ca 2 Nb 3 O 10 (CNO) and three–dimensional (3D) KCa 2 Nb 3 O 10 (KCNO) perovskite oxides as well–defined model systems. The 2D Au/CNO catalyst demonstrated a marked enhancement in CO 2 RR performance, achieving a higher CO Faradaic efficiency (FE) than that of the 3D Au/KCNO catalyst. We revealed that the enhanced activity of Au/CNO is attributed to a higher proportion of partially oxidized Au species (Au δ+ ) and improved interfacial electronic polarization of Au on CNO. These findings underscore the importance of the oxide support structure in modulating electronic environments and metal–oxide interactions, providing new insights for the rational design of efficient CO 2 RR catalysts.