在金属间Pt3Ga上提高原子层Pt的电氧化性能
Quanchen Feng1, Shu Zhao2, Dongsheng He3
1Department of Chemistry, Tsinghua University , Beijing 100084, China.
Journal of the American Chemical Society
|February 13, 2018
概括
这项研究将拉伸式 (Pt) 引入 (Pt3Ga) 作为甲醇氧化反应 (MOR) 的优质电催化剂. 由于电子性能优化,工程催化剂具有增强的活性和耐用性.
科学领域:
- 材料科学
- 电化学
- 表面科学
背景情况:
- 应变工程是优化材料催化性能的一个关键策略.
- 甲醇氧化反应 (MOR) 对燃料电池至关重要,但需要高效的电催化剂.
- 基材料广泛用于MOR,但它们的活性和稳定性需要改进.
研究的目的:
- 使用应变工程开发和描述一种用于MOR的新型电催化剂.
- 研究拉伸应变对的催化性能的影响.
- 了解催化剂增强活性背后的机制.
主要方法:
- 在金属间Pt3Ga (AL-Pt/Pt3Ga) 上制造两到三原子层.
- 原子分辨率高角度环状暗场扫描传输电子显微镜 (HAADF-STEM) 用于应变分析.
- 电化学测试以评估MOR的活性和性能.
- 密度函数理论 (DFT) 的计算以阐明反应机制.
主要成果:
- AL-Pt/Pt3Ga 在 [001] 方向上表现出 3.2% 的拉伸力.
- 与未应力Pt和商业Pt/C相比,应力催化剂的特异活性 (7.195 mA cm−2) 和质量活性 (1.094 mA/μgPt) 显著提高.
- DFT的计算证实了拉力应变有利于MOR,因为它加强OH*结合并促进CO*的去除.
结论:
- 对AL-Pt/Pt3Ga的拉伸应变工程是一种有效的方法来增强MOR电催化.
- 这种性能提升归因于电子结构的改变和优化的吸附能.
- 这项工作为燃料电池应用设计先进的电催化剂提供了洞察力.
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