通过表面探测扫描电化学显微镜对的进化反应机制的研究
Zhenxing Liang1, Hyun S Ahn2, Allen J Bard1
1Center for Electrochemistry, Department of Chemistry, The University of Texas at Austin , Austin, Texas 78712, United States.
Journal of the American Chemical Society
|March 10, 2017
概括
在 (Ni) 上的演化反应 (HER) 被低价位氧化增强. 这项研究使用扫描电化学显微镜揭示了吸附是基媒介中HER的速度限制步骤.
科学领域:
- 电化学
- 材料科学
- 表面科学
背景情况:
- 进化反应对于可持续能源技术至关重要.
- (Ni) 是性介质中HER的一个有前途的电催化剂.
- 了解Ni表面上的HER机制对于催化剂优化至关重要.
研究的目的:
- 在性介质中研究Ni对HER的电催化活性.
- 阐明氧化在增强HER中的作用.
- 确定HER在Ni上的速度决定性步骤.
主要方法:
- 在基板生成/尖端采集模式下扫描电化学显微镜 (SECM).
- 用于测量吸附覆盖面的表面探测SECM (SI-SECM).
- 电化学分析包括极化曲线和塔菲尔斜率的确定.
主要成果:
- 与金属相比,低价位氧化物显著提高了HER的电催化活性.
- 在Ni上的吸附覆盖遵循弗鲁姆金等温.
- 水的分离吸附在Ni/Ni氧化物界面上得到增强.
结论:
- 氧化的存在通过促进水分离增强了HER活性.
- 在研究的潜在窗口中,对HER的速度决定的步骤是吸附 (Volmer步骤).
- 对于电化学反应的机理研究来说,SECM是一个强大的工具.
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