Choi, Hansol Shin, Seung-Jae Bae, Geunsu Cho, Junsic Han, Man Ho Sougrati, Moulay Tahar Jaouen, Frederic Lee, Kug-Seung Oh, Hyung-Suk Kim, Hyungjun Choi, Chang Hyuck 2025-05-11T06:00:50Z 2025-05-11T06:00:50Z 2025-05-07 2025-04 0002-7863 https://pubs.kist.re.kr/handle/201004/152414 Potential-induced electrode charging is a prerequisite to initiate electrochemical reactions at the electrode-electrolyte interface. The 'interface space charge' could dramatically alter the reaction environment and the charge density of the active site, both of which potentially affect the electrochemical activity. However, our understanding of the electrocatalytic role of space charge has been limited. Here, we separately modulate the amount of space charge (characterized by the areal density, sigma) with maintaining the electrochemical potential for the oxygen reduction reaction (ORR) at the same level, by exploiting the unique structural feature of MeNC. We reveal that changes in sigma control the ORR activity, which is computationally explained by the inductive polarization of the charge density at the active sites, affecting their turnover rates. To guide catalyst design including the space charge effect, we develop a new descriptor, explaining the activity trend in various metal centers and pH conditions using a single volcano. These findings offer fresh insights into the role of space charge in electrocatalysis, providing a new framework for optimizing catalyst design and performance. English American Chemical Society Space Charge, Modulating the Catalytic Activity of Single-Atom Metal Catalysts Article 10.1021/jacs.4c17413 1 Journal of the American Chemical Society, v.147, no.16, pp.13220 - 13228 Journal of the American Chemical Society 147 16 13220 13228 N scie scopus 001466594500001 2-s2.0-105003436854 Chemistry, Multidisciplinary Chemistry Article IRON-BASED CATALYSTS WORK FUNCTION DENSITY-FUNCTIONAL THEORY OXYGEN REDUCTION ACTIVITY NO REDUCTION NITROGEN IDENTIFICATION CONVERSION SITES ORR