Department of Chemistry, University of Washington, Seattle, Washington 98195 United States.
Anal Chem. 2020 May 5;92(9):6748-6755. doi: 10.1021/acs.analchem.0c00921. Epub 2020 Apr 13.
In this report, we describe the fabrication, characterization, and use of a massive array of closed bipolar ultramicroelectrodes (UMEs) in electrochemical imaging applications. The bipolar UME array is 1 cm in size and contains >146 000 carbon electrodes embedded in a 15 μm thick insulating and freestanding membrane of Parylene C. Structural characterization with optical and electron microscopies shows that the carbon UMEs are highly uniform in size, shape, and interelectrode spacing. The bipolar UME array was used in electrochemical imaging to probe highly dynamic redox processes in which the reduction of redox molecules on one side the array is electrically coupled to an oxidative electrochemilumescence (ECL) process on the opposite side. This allows one to simultaneously monitor electrochemical reactions on hundreds of thousands of individual electrodes with millisecond temporal resolution. Our results suggest that microfabricated closed bipolar UME arrays can be useful for imaging fast and transient electrochemical processes in which scanning probe methods are inapplicable due to their limited temporal resolution.
在本报告中，我们描述了大规模闭双极超微电极（UME）阵列的制造、表征和在电化学成像应用中的使用。双极 UME 阵列大小为 1 厘米，包含嵌入在聚对二甲苯 C 厚 15 µm 的绝缘和独立膜中的 >146000 个碳电极。光学和电子显微镜的结构表征表明，碳 UME 在尺寸、形状和电极间距方面具有高度的均匀性。双极 UME 阵列用于电化学成像，以探测高度动态的氧化还原过程，其中阵列一侧的氧化还原分子的还原与另一侧的电致化学发光（ECL）过程电偶联。这使得人们能够以毫秒的时间分辨率同时监测数十万个体电极上的电化学反应。我们的结果表明，微制造的闭双极 UME 阵列可用于成像快速和瞬态的电化学过程，由于其时间分辨率有限，扫描探针方法在这些过程中不适用。
