实时KMC模拟空隙介导混合在Au@Ag八面体核心立方纳米晶体与Ab Initio引导的动力学
Yong Han1,2, James W Evans1,2
1Ames National Laboratory, US Department of Energy, Ames, Iowa 50011, United States.
ACS nano
|July 31, 2024
概括
这项研究引入了一个新的原子学模型来预测核心纳米晶体随着时间的推移如何变化. 该模型准确地捕捉了金银纳米晶体的混合,揭示了控制物质降解的关键因素.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术 纳米技术
- 计算化学计算化学
背景情况:
- 核心外纳米晶体 (NCs) 提供可调节的特性,但易受通过混合的组成变化.
- 混合可以降低NC在各种应用中的性能.
- 以前的建模方法在准确性和范围上存在局限性.
研究的目的:
- 开发一个预测性,原子级模型,用于核心外NC中空位介导的混合.
- 将初始密度功能理论计算用于热力学和扩散障碍的计算纳入.
- 了解混合的时间尺度和速率控制过程.
主要方法:
- 开发了一个空位介导混合的随机模型.
- 集成的初始密度功能理论 (DFT) 用于空缺形成和扩散障碍.
- 在相关时间尺度 (10^1-10^3秒) 上模拟混合.
- 将模型应用于金银 (Au@Ag) 核心外纳米晶体.
主要成果:
- 该模型准确地预测了60nm Au@Ag NCs在450°C下实验观察到的~100s的混合时间尺度.
- 阐明了控制混合的特定速率控制过程.
- 根据原子相互作用确定了有效的混合屏障.
结论:
- 开发的模型提供了一个全面的理解,混合在核心外NCs.
- 这种方法克服了以前通用或连续模型的局限性.
- 能够预测纳米晶体稳定性和特性演变的预测洞察力,用于定制的应用.
更多相关视频
10:52Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics
Published on: April 12, 2019
12.8K
07:24Quantitative Atomic-Site Analysis of Functional Dopants/Point Defects in Crystalline Materials by Electron-Channeling-Enhanced Microanalysis
Published on: May 10, 2021
5.9K
相关概念视频
Hybridization of Atomic Orbitals II
32.0K
sp3d and sp3d 2 Hybridization
32.0K
Hybridization of Atomic Orbitals I
46.7K
The mathematical expression known as the wave function, ψ, contains information about each orbital and the wavelike properties of electrons in an isolated atom. When atoms are bound together in a molecule, the wave functions combine to produce new mathematical descriptions that have different shapes. This process of combining the wave functions for atomic orbitals is called hybridization and is mathematically accomplished by the linear combination of atomic orbitals. The new orbitals that...
46.7K
Fermi Level Dynamics
229
The vacuum level denotes the energy threshold required for an electron to escape from a material surface. It is usually positioned above the conduction band of a semiconductor and acts as a benchmark for comparing electron energies within various materials.
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
229
Van der Waals Interactions
63.7K
Atoms and molecules interact with each other through intermolecular forces. These electrostatic forces arise from attractive or repulsive interactions between particles with permanent, partial, or temporary charges. The intermolecular forces between neutral atoms and molecules are ion–dipole, dipole–dipole, and dispersion forces, collectively known as van der Waals forces.
63.7K
Crystal Field Theory - Octahedral Complexes
26.3K
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
26.3K
Equilibrium Conditions for a Particle
1.1K
When an object is in equilibrium, it is either at rest or moving with a constant velocity. There are two types of equilibrium: static and dynamic. Static equilibrium occurs when an object is at rest, while dynamic equilibrium occurs when an object is moving with a constant velocity. In both cases, there must be a balance of forces acting on the object.
To understand the concept of equilibrium, let us first consider the forces acting on an object. When different forces act on an object, they can...
To understand the concept of equilibrium, let us first consider the forces acting on an object. When different forces act on an object, they can...
1.1K
