在硅窗口上进行TiO的原子层沉积可实现强碱性电解质中的衰减全反射表面增强红外吸收光谱（ATR-SEIRAS）测量。

Atomic Layer Deposition of TiO on Si Window Enables ATR-SEIRAS Measurements in Strong Alkaline Electrolytes.

作者信息

Zhang Wei-Yi, Ma Xian-Yin, Jiang Tian-Wen, Xu Xindi, Ni Baoxin, Chen Bin, Wang Yunyu, Jiang Kun, Cai Wen-Bin

机构信息

Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Collaborative Innovation Center of Chemistry for Energy Materials, Department of Chemistry, Fudan University, Shanghai 200438, China.

Interdisciplinary Research Center, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.

出版信息

Anal Chem. 2024 Jun 25;96(25):10111-10115. doi: 10.1021/acs.analchem.4c01985. Epub 2024 Jun 13.

DOI:10.1021/acs.analchem.4c01985

PMID:38869290

Abstract

The Si window is the most widely used internal reflection element (IRE) for electrochemical attenuated total reflection surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS), yet local chemical etching on Si by concentrated OH anions bottlenecks the reliable application of this method in strong alkaline electrolytes. In this report, atomic layer deposition of a 25 nm nonconductive TiO barrier layer on the reflecting plane of a Si prism is demonstrated to address this challenge. ATR-SEIRAS measurement on a Au film electrode with the Si/TiO composite IRE in 1 M NaOH reveals reversible global spectral features without spectral distortion at 1000-1300 cm, in stark contrast to those obtained with a bare Si window. By applying this structured ATR-SEIRAS, ethanol electrooxidation on a Pt/C catalyst in 1 and 5 M NaOH is explored, manifesting that such high pH values prevent the adsorption of as-formed acetate in the C2 pathway but not that of CO intermediate in the C1 pathway.

摘要

硅窗口是用于电化学衰减全反射表面增强红外吸收光谱（ATR-SEIRAS）的最广泛使用的内反射元件（IRE），然而，浓OH阴离子对硅的局部化学蚀刻限制了该方法在强碱性电解质中的可靠应用。在本报告中，证明了在硅棱镜的反射面上原子层沉积25 nm的非导电TiO阻挡层可以应对这一挑战。在1 M NaOH中使用Si/TiO复合IRE对金膜电极进行ATR-SEIRAS测量，发现在1000-1300 cm处具有可逆的整体光谱特征且无光谱畸变，这与使用裸硅窗口获得的结果形成鲜明对比。通过应用这种结构化的ATR-SEIRAS，研究了在1 M和5 M NaOH中Pt/C催化剂上的乙醇电氧化，表明如此高的pH值会阻止C2途径中生成的乙酸盐的吸附，但不会阻止C1途径中CO中间体的吸附。