尺寸和形状对Ni-Pt纳米合金中的化学排序的影响
Pamela Camilos1, Céline Varvenne1,2, Christine Mottet1
1Aix-Marseille University/CNRS, CINaM UMR 7325, Campus de Luminy, Marseille 13288, France. christine.mottet@univ-amu.fr.
Physical chemistry chemical physics : PCCP
|May 20, 2024
概括
数字模拟显示,- (Ni-Pt) 纳米合金表现出复杂的原子排序和表面分离. 由于原子应变效应,异形形状特别促进金表面分离.
科学领域:
- 材料科学 材料科学 材料科学
- 计算化学的计算化学
- 纳米技术纳米技术
背景情况:
- 了解纳米合金的原子结构和化学排序对于设计先进材料至关重要.
- -白金 (Ni-Pt) 合金由于其独特的特性而引起人们的兴趣,但它们在纳米尺度上的行为是复杂的.
研究的目的:
- 研究Ni-Pt纳米合金的原子结构和化学排序.
- 探索大小,形状和温度对合金行为的影响.
- 了解这些纳米粒子中的表面分离现象.
主要方法:
- 使用蒙特卡洛方法进行数值模拟.
- 对Ni-Pt相互作用应用一个现实的原子间潜力.
- 分析不同尺寸和形状的纳米粒子,包括二面体,八面体和截断的八面体结构.
主要成果:
- 在面中心立方 (fcc) 纳米粒子中,Ni-Pt纳米合金保留了批量订购趋势.
- 表面重建导致化学排序挫折,取决于集群大小和形状.
- 观察到 (Pt) 表面分离的反向温度依赖.
- 在icosahedral纳米粒子中,Ni因原子应变而分离到核心,而Pt则分离到表面.
- 与八面体和截断的八面体结构相比,二面体形状促进了Pt表面分离.
结论:
- Ni-Pt纳米合金的原子结构和化学排序受到大小,形状和温度的显著影响.
- 表面效应和原子应变在分离行为中起着至关重要的作用,特别是在非散装结构的结构中,例如icosahedra.
- 形状依赖的分离现象为定制纳米合金特性提供了途径.
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