单个原子合金在质的存在下进行分离
Maya Salem1, Dennis J Loevlie1, Giannis Mpourmpakis1
1Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States.
The journal of physical chemistry. C, Nanomaterials and interfaces
|December 1, 2023
概括
来自纳米粒子合成的体通过改变表面分离,显著影响单原子合金的稳定性. 机器学习模型预测了这些效应,使得稳定的合体单原子合金的有效选成为可能.
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) 为增强催化提供可调性特性,但它们的稳定性对表面分离敏感.
- 关于SAA稳定性的现有研究主要研究常见的反应中间体 (CO,H),忽略了纳米粒子合成的配体.
- 了解连接体效应对于控制SAA在合体系统中的稳定性至关重要.
研究的目的:
- 研究醇和氨基联体对合体SAA表面分离和稳定性的影响.
- 开发SAA稳定性的预测模型,在有连接体的情况下.
主要方法:
- 密度函数理论 (DFT) 计算以获得各种具有和没有连接体的SAA的分离能量 (E_seg).
- 开发一个四特征神经网络 (NN MLP) 模型,包括凝聚能,协调数,结合强度,维格纳-赛茨半径和电子亲和力.
- 使用DFT数据进行机器学习模型培训和验证.
主要成果:
- 与赤裸的SAA表面相比,连接物存在通常会导致较温和的分离热力学.
- 吸附配置和连接体结合强度 (胺基与醇) 显著改变分离能量趋势.
- 开发的NN MLP模型准确地预测E_seg在配体的存在下,捕获实验观测.
结论:
- 干体在控制合体SAA的表面分离和稳定性方面发挥着至关重要的作用.
- 预测模型有助于快速有效地选热力学稳定的SAA.
- 这项工作阐明了与催化相关的纳米级接口分离的复杂物理.
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