从X射线视频中学习异质反应动力学
Hongbo Zhao1, Haitao Dean Deng2, Alexander E Cohen1
1Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA.
Nature
|September 13, 2023
概括
研究人员开发了一种基于数据的新方法来量化复杂材料接口的反应速率, 这对于电池和催化剂至关重要. 这种方法从显微镜图像中准确地学习异质动力学,进步了材料科学.
科学领域:
- 材料科学
- 化学工程
- 数据科学
背景情况:
- 在异质,不稳定的接口上量化反应速率具有挑战性,但对于电池和电催化剂等应用至关重要.
- 操作显微镜可以产生丰富的图像数据,但由于复杂的合,缺乏数据驱动的方法来提取底层物理.
- 现有的方法与反应动力学,表面化学和相分离的复杂相互作用作斗争.
研究的目的:
- 从现场显微镜图像学习异质反应动力学的数据驱动方法.
- 提取具有复杂接口的材料的自由能量场景和反应动力学.
- 用非破坏性方式描述和优化异质反应表面.
主要方法:
- 使用现场扫描传输X射线显微镜 (STXM) 对碳涂层铁 (LFP) 纳米颗粒的图像.
- 结合大型STXM图像数据集与热力学一致的电化学相场模型.
- 使用部分微分方程 (PDE) 约束优化和不确定性量化.
主要成果:
- 从STXM图像中成功学习了异质反应动力学,与碳涂层厚度密切相关.
- 提取了自由能景观和反应动力学,与理论模型一致.
- 在18万像素的平均差异<7%,相当于实验噪声.
结论:
- 开发的方法使得学习非平衡材料的特性超出了传统的实验范围.
- 提供了一种新的非破坏性技术,用于表征和优化异质反应表面.
- 促进对储能和催化材料的理解和工程.
相关概念视频
Measuring Reaction Rates
25.3K
Polarimetry finds application in chemical kinetics to measure the concentration and reaction kinetics of optically active substances during a chemical reaction. Optically active substances have the capability of rotating the plane of polarization of linearly polarized light passing through them—a feature called optical rotation. Optical activity is attributed to the molecular structure of substances. Normal monochromatic light is unpolarized and possesses oscillations of the electrical...
25.3K
Introduction to Enzyme Kinetics
20.1K
Enzyme kinetics studies the rates of biochemical reactions. Scientists monitor the reaction rates for a particular enzymatic reaction at various substrate concentrations. Additional trials with inhibitors or other molecules that affect the reaction rate may also be performed.
The experimenter can then plot the initial reaction rate or velocity (Vo) of a given trial against the substrate concentration ([S]) to obtain a graph of the reaction properties. For many enzymatic reactions involving a...
The experimenter can then plot the initial reaction rate or velocity (Vo) of a given trial against the substrate concentration ([S]) to obtain a graph of the reaction properties. For many enzymatic reactions involving a...
20.1K
SN2 Reaction: Kinetics
8.5K
Kinetic Studies and Significance
In a chemical reaction, a relationship exists between the concentration of reactants and the rate at which the reaction proceeds. The study to measure this relationship is known as the kinetics of a chemical reaction. Kinetic studies are used to deduce the rate law of a chemical reaction, which provides information about the species involved during the transition state of the rate-determining step. Thus, kinetic studies help to derive the mechanism of a...
In a chemical reaction, a relationship exists between the concentration of reactants and the rate at which the reaction proceeds. The study to measure this relationship is known as the kinetics of a chemical reaction. Kinetic studies are used to deduce the rate law of a chemical reaction, which provides information about the species involved during the transition state of the rate-determining step. Thus, kinetic studies help to derive the mechanism of a...
8.5K
E1 Reaction: Kinetics and Mechanism
15.5K
Here, in contrast to the E2 reaction mechanism, we delve into the aspects of the E1 reaction mechanism, which has two steps: rate-limiting loss of the leaving group and abstraction of the beta hydrogen by a weak base. Typically, the experimental proof for the E1 mechanism is via kinetic studies or isotope studies. While the former demonstrates the first-order kinetics—the dependence of the reaction solely on substrate concentration—the latter proves the abstraction of hydrogen only...
15.5K
Predicting Reaction Outcomes
8.5K
Kinetics describes the rate and path by which a reaction occurs. In contrast, thermodynamics deals with state functions and describes the properties, behavior, and components of a system. It is not concerned with the path taken by the process and cannot address the rate at which a reaction occurs. Although it does provide information about what can happen during a reaction process, it does not describe the detailed steps of what appears on an atomic or a molecular level. On the other hand,...
8.5K
Enzyme Kinetics
97.1K
Enzymes speed up reactions by lowering the activation energy of the reactants. The speed at which the enzyme turns reactants into products is called the rate of reaction. Several factors impact the rate of reaction, including the number of available reactants. Enzyme kinetics is the study of how an enzyme changes the rate of a reaction.
Scientists typically study enzyme kinetics with a fixed amount of enzyme in the controlled environment of a test tube. When more reactant, or substrate, is...
Scientists typically study enzyme kinetics with a fixed amount of enzyme in the controlled environment of a test tube. When more reactant, or substrate, is...
97.1K


