Substrate Selection for Fundamental Studies of Electrocatalysts and Photoelectrodes: Inert Potential Windows in Acidic, Neutral, and Basic Electrolyte

The selection of an appropriate substrate is an important initial step for many studies of electrochemically active materials. In order to help researchers with the substrate selection process, we employ a consistent experimental methodology to evaluate the electrochemical reactivity and stability of seven potential substrate materials for electrocatalyst and photoelectrode evaluation. Using cyclic voltammetry with a progressively increased scan range, we characterize three transparent conducting oxides (indium tin oxide, fluorine-doped tin oxide, and aluminum-doped zinc oxide) and four opaque conductors (gold, stainless steel 304, glassy carbon, and highly oriented pyrolytic graphite) in three different electrolytes (sulfuric acid, sodium acetate, and sodium hydroxide). We determine the inert potential window for each substrate/electrolyte combination and make recommendations about which materials may be most suitable for application under different experimental conditions. Furthermore, the testing methodology provides a framework for other researchers to evaluate and report the baseline activity of other substrates of interest to the broader community.

对于诸多电化学活性材料的相关研究而言，选取合适的基底是至关重要的初始环节。为协助研究人员完成基底筛选工作，我们采用统一的实验方法，对可用于电催化剂与光电极评价的7种潜在基底材料的电化学反应性与稳定性开展评估。我们采用逐步增大扫描范围的循环伏安法（Cyclic Voltammetry），在硫酸、乙酸钠、氢氧化钠三种不同电解液中，对3种透明导电氧化物（Transparent Conducting Oxides）——氧化铟锡（Indium Tin Oxide）、氟掺杂氧化锡（Fluorine-doped Tin Oxide）与铝掺杂氧化锌（Aluminum-doped Zinc Oxide）——以及4种不透明导体：金（Gold）、304不锈钢（Stainless Steel 304）、玻璃碳（Glassy Carbon）、高定向热解石墨（Highly Oriented Pyrolytic Graphite）进行表征。我们测定了每种基底-电解液组合的惰性电位窗口，并针对不同实验场景下的适配材料给出针对性推荐方案。此外，本测试方法还为其他研究人员提供了一套标准化评估框架，用以对其科研兴趣范围内的其他基底的本征活性进行评估与报告，供更广的科研社区参考。