通过高合金的元素调来定制局部化学排序
Zhennan Huang1, Tangyuan Li1, Boyang Li2
1Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States.
Journal of the American Chemical Society
|January 12, 2024
概括
高合金 (HEAs) 具有很大的潜力,但它们的局部原子结构尚不清楚. 这项研究揭示了元素变化如何极大地改变HEA结构,使得纳米材料的催化性能能够得到控制.
科学领域:
- 材料科学
- 纳米技术
- 催化剂
背景情况:
- 高合金 (HEAs) 为高级应用提供了广泛的组成可能性.
- 了解HEAs中的局部原子和元素配置,特别是基于贵金属的纳米材料,至关重要但具有挑战性.
- 目前的知识差距阻碍了纳米HEAs的合理设计,用于能量转化和催化.
研究的目的:
- 准确确定模型高温电池 (RhPtPdFeCo和RuPtPdFeCo) 的原子级结构和元素安排.
- 研究单元替代对元素分布和排序的影响.
- 通过调整元素度来证明HEAs的局部排序.
主要方法:
- 高合金纳米材料模型的合成.
- 先进的特征技术探测原子层结构和元素分布.
- 构成元素及其度的系统变化.
主要成果:
- 在HEAs中用Ru替换Rh导致从随机混合到局部元素排序的显著变化.
- 含有Ru的HEAs的局部排序可以通过改变Ru度来调整.
- 能够控制局部Ru集群并形成独特的异构结构.
结论:
- 开发了一种用于操纵贵金属基高温电池的局部原子结构和元素排列的实用方法.
- 提供了对HEA纳米材料结构属性关系的基本见解.
- 在催化和能量转换中为HEAs的机制理解和设计奠定了基础.
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