文献类型：期刊文献

英文题名：Confirmation of the rate-determining step for ORR in the high potential region: adsorption process of oxygen molecules on the catalyst surface

作者：Zeng, Jiaxi[1];Lu, Jiyuan[1];Zhang, Lili[1];Yang, Jiajia[1];Yu, Shengwei[2];Jiang, Haibo[1]

机构：[1]East China Univ Sci & Technol, Key Lab Ultrafine Mat, Shanghai Engn Res Ctr Hierarch Nanomat, Sch Mat Sci & Engn,Minist Educ, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Sch Chem Engn, Shanghai 200237, Peoples R China

年份：2025

卷号：27

期号：31

起止页码：16295

外文期刊名：PHYSICAL CHEMISTRY CHEMICAL PHYSICS

收录：;EI(收录号：20253218942978);WOS:【SCI-EXPANDED(收录号:WOS:001532411500001)】；

语种：英文

外文关键词：Activation energy - Binary alloys - Catalysts - Gas adsorption - Oxygen - Oxygen reduction reaction - Platinum - Platinum alloys - Platinum compounds - Reaction kinetics

摘要：The oxygen reduction reaction kinetics at low overpotentials (<15 mV vs. OCP) were investigated using PtNi and PtPb catalysts, revealing near-zero H+ (0.05-0.12) and first O-2 (0.89-1.02) reaction orders, which conclusively identify O-2 adsorption as the rate-determining step. Notably, PtNi demonstrated the lowest activation energy (21.81 kJ mol(-1)vs. 22.48 for Pt/C and 24.73 for PtPb), which was directly correlated with its narrower HOMO-LUMO gap (-1.02 eV). This reduced orbital energy spacing facilitates electron flow during the chemical adsorption process, destabilizing transition states and lowering activation barriers.