在Pt的初始氧化过程中的表面提取过程:性介质中性/性的作用
Tomoaki Kumeda1, Kenshin Kondo1, Syunnosuke Tanaka1
1Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
Journal of the American Chemical Society
|March 20, 2024
概括
阴离子类型会影响电极的氧化. 像Li+这样的水友性离子稳定氧化物,防止Pt提取,而疏水性TMA+则抑制Pt溶解氧化物形成,这对于稳定的电催化剂至关重要.
科学领域:
- 表面科学
- 电化学
- 材料科学
背景情况:
- 金属电极的表面氧化对于电催化剂的性能,选择性和稳定性至关重要.
- 了解氧化物形成和减少是开发先进电催化剂的关键.
研究的目的:
- 在性介质中研究 (Pt(111) 的初始电化学氧化.
- 确定对表面氧化过程和由此产生的结构的水友性和疏水性离子的作用.
主要方法:
- 使用X射线晶体截断棒 (CTR) 散射进行结构确定.
- 使用红外 (IR) 光谱和表面增强的拉曼光谱 (SERS) 进行振动分析.
- 在性溶液中研究了Pt111氧化,类型不同 (Li+,TMA+,K+).
主要成果:
- 在初始氧化过程中,X射线CTR显示了离子依赖的表面曲和Pt提取.
- 振动光谱检测发现了三种不同的氧化物 (IR活性OHad,拉曼活性OHad/Oad ((H2O),拉曼活性Oad).
- 水性Li+通过稳定红外活性OHad来抑制粗化,阻碍Pt提取.
- 通过抑制Raman活性OHad/Oad (H2O) 的形成,水性TMA+减少了不可逆转的氧化.
- 离子 (K+) 没有保护作用,通过共吸收作用促进Pt提取.
结论:
- 在电催化剂氧化过程中,阴离子选择显著控制了表面结构的演变.
- 水友性和疏水性提供不同的机制来减轻有害的Pt提取.
- 通过电离子工程提高了电催化剂的稳定性.
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