单原子合金聚合在连接体的存在下
Maya Salem1, Giannis Mpourmpakis1
1Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, USA. gmpourmp@pitt.edu.
Nanoscale
|January 20, 2025
概括
干稳定单原子合金 (SAA) 通过防止剂聚合,这对于催化至关重要. 本研究使用DFT和ML来预测聚合能量,指导稳定的SAA设计.
科学领域:
- 材料科学 材料科学 材料科学
- 表面科学是一门学科.
- 计算化学的计算化学
背景情况:
- 单原子合金 (SAA) 由于在宿主金属表面上分离的活性剂,具有独特的催化性能.
- SAA的稳定性取决于多邦特表面分离和聚合能,对对联体对聚合的影响的理解有限.
- 像醇和氨酸这样的配体在合成合体双金属纳米颗粒中很常见,影响SAA的稳定性.
研究的目的:
- 为了研究结合和非结合SAA中的兴奋剂的聚合能量 (E_agg).
- 探索常见的连接物 (醇,氨基) 如何影响金属表面上的多聚合物.
- 开发SAA稳定性的预测模型并指导实验设计.
主要方法:
- 密度函数理论 (DFT) 计算以确定各种金属组合 (d8: Pt, Pd, Ni; d9: Ag, Au, Cu) 的低指数表面的能量 ((111), (100)).
- 机器学习 (ML),特别是支持向量回归 (SVR RBF),在DFT数据上进行训练,以预测E_agg.
- 在ML模型中包括金属凝聚能,电荷转移,原子半径和连接体结合能等特征.
主要成果:
- 开发了一个强大的ML模型来预测E_agg,确定驱动金属聚合的关键热力学稳定性特征.
- 干通过减少多邦聚合来稳定SAA,特别是在基于Ni,Pd和Pt的系统中.
- 具有Ni,Pd或Pt的Ag,Au和Cu合的SAA倾向于聚合,表明没有特定稳定策略的不稳定性.
结论:
- 连接物通过抑制多聚合物聚合,在稳定单原子合金中发挥关键作用.
- 开发的ML模型准确预测SAA稳定性,并可以快速选潜在的SAA候选人.
- 这项工作提供了稳定SAA的标准,促进了催化应用的合理设计.
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