过电位
塔菲尔方程
铂金
化学
无机化学
电催化剂
电化学
氢铵
电解质
电极
旋转圆盘电极
电子转移
离子
催化作用
循环伏安法
光化学
物理化学
有机化学
作者
Tatsuya Shinagawa,Angel T. Garcia‐Esparza,Kazuhiro Takanabe
标识
DOI:10.1002/celc.201402085
摘要
Abstract Fundamental electrochemical reactions, namely the hydrogen evolution reaction (HER) and the hydrogen oxidation reaction (HOR), are re‐evaluated under various pH conditions over polycrystalline Pt disk electrodes and Pt/C electrodes to investigate the overpotential and Tafel relations. Kinetic trends are observed and can be classified into three pH regions: acidic (1–5), neutral (5–9), and alkaline (9–13). Under neutral conditions, in which H 2 O becomes the primary reactant, substantial overpotential, which is not affected by pH and the supporting electrolyte type, is required for electrocatalysis in both directions. This ion independence, including pH, suggests that HER/HOR performance under neutral conditions solely reflects the intrinsic electrocatalytic activity of Pt in the rate determining steps, which involve electron transfer with water molecules. A global picture of the HER/HOR, resulting from mechanistic switching accompanied by change in pH, is detailed.
科研通智能强力驱动
Strongly Powered by AbleSci AI