在有孔的涂层电极上单分子电化学
Jin Lu1, Yunshan Fan1, Marco D Howard1
1Department of Chemistry, University of Washington , Seattle, Washington 98195-1700, United States.
Journal of the American Chemical Society
|January 31, 2017
概括
研究人员使用纳米通道和光分子直接观察了氧化物 (ITO) 电极上的单一氧化还原事件. 这种方法可以在单个分子水平上详细研究电化学动力学.
科学领域:
- 电化学
- 表面科学
- 纳米技术
背景情况:
- 研究单一的氧化还原事件提供了对电化学过程的基本见解.
- 传统的方法通常是平均信号,掩盖异质动力学.
- 纳米封闭提供了一种隔离和分析单个分子事件的途径.
研究的目的:
- 在改造的氧化 (ITO) 电极上直接观察和量化单个氧化还原事件.
- 使用纳米封闭的二氧化通道和氧化还原物种来增强单分子检测.
- 在单个分子水平上研究Resorufin的吸附,脱附和氧化还原动力学.
主要方法:
- 通过电化学过程在 ITO 电极上制造具有并行纳米通道 (∼3 nm直径) 的超薄片.
- 使用全内部反射光显微镜 (TIRF) 进行单分子观测.
- 采用单分子光电量测量来分析氧化还原事件和电化学动力学.
主要成果:
- 在3纳米纳米通道内成功封闭光素分子,使单分子研究成为可能.
- 分别为 (1.73 ± 0.08) × 10 cm·s-1 和 15.71 ± 0.76 s-1 的量化吸附和脱吸速率常数.
- 通过扫描速度依赖的分子计数来证明表面控制的电化学动力学.
结论:
- 在透明导电基板上研究单次氧化还原事件时,中孔膜是有效的.
- 开发的方法允许在单个分子水平上详细分析吸附,脱附和氧化还原过程.
- 这种方法有可能研究电催化表面的空间异质性.
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