Costentin Cyrille, Porter Thomas R, Savéant Jean-Michel
Université Paris Diderot, Sorbonne Paris Cité, Laboratoire d'Electrochimie Moléculaire, Unité Mixte de Recherche Université - CNRS No 7591 , Bâtiment Lavoisier, 15 rue Jean de Baïf , 75205 Paris Cedex 13, France.
ACS Appl Mater Interfaces. 2019 Aug 14;11(32):28769-28773. doi: 10.1021/acsami.9b05240. Epub 2019 Jul 30.
The transition between the insulator state and the band-conducting state is investigated by means of cyclic voltammetry in cobalt oxide porous film electrodes in phosphate-buffered solutions. It is shown that a proton-coupled faradaic oxidative process starting in the insulator region eventually builds an ohmic conduction mode upon anodic polarization. This model allows one to understand the origin of the authentic capacitive behavior of conductive metal oxide films rather than the so-called "pseudocapacitive" behavior. The particular example of cobalt oxide serves to illustrate the way in which, more generally, the behavior of "pseudocapacitors", long ascribed to the superposition of faradaic reactions, is in fact that of true capacitors, once band-conduction has been established upon oxidation of the material.
在磷酸盐缓冲溶液中的氧化钴多孔膜电极中，通过循环伏安法研究了绝缘体状态和带导电状态之间的转变。结果表明，在绝缘体区域开始的质子耦合法拉第氧化过程最终在阳极极化时建立了欧姆传导模式。该模型使人们能够理解导电金属氧化物薄膜真实电容行为的起源，而不是所谓的“赝电容”行为。氧化钴的具体例子说明了这样一种方式，即更一般地说，长期以来归因于法拉第反应叠加的“赝电容器”行为，实际上是一旦材料氧化后建立了带传导，就成为了真正电容器的行为。
