{"title":"Ab initio 分子动力学模拟揭示了熵效应对 Co@BEA 沸石催化乙烷脱氢反应的影响","authors":"","doi":"10.1016/S1872-2067(24)60116-6","DOIUrl":null,"url":null,"abstract":"<div><div>The C–H bond activation in alkane dehydrogenation reactions is a key step in determining the reaction rate. To understand the impact of entropy, we performed ab initio static and molecular dynamics free energy simulations of ethane dehydrogenation over Co@BEA zeolite at different temperatures. AIMD simulations showed that a sharp decrease in free energy barrier as temperature increased. Our analysis of the temperature dependence of activation free energies uncovered an unusual entropic effect accompanying the reaction. The unique spatial structures around the Co active site at different temperatures influenced both the extent of charge transfer in the transition state and the arrangement of 3<em>d</em> orbital energy levels. We provided explanations consistent with the principles of thermodynamics and statistical physics. The insights gained at the atomic level have offered a fresh interpretation of the intricate long-range interplay between local chemical reactions and extensive chemical environments.</div></div>","PeriodicalId":9832,"journal":{"name":"Chinese Journal of Catalysis","volume":null,"pages":null},"PeriodicalIF":15.7000,"publicationDate":"2024-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Ab initio molecular dynamics simulation reveals the influence of entropy effect on Co@BEA zeolite-catalyzed dehydrogenation of ethane\",\"authors\":\"\",\"doi\":\"10.1016/S1872-2067(24)60116-6\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"<div><div>The C–H bond activation in alkane dehydrogenation reactions is a key step in determining the reaction rate. To understand the impact of entropy, we performed ab initio static and molecular dynamics free energy simulations of ethane dehydrogenation over Co@BEA zeolite at different temperatures. AIMD simulations showed that a sharp decrease in free energy barrier as temperature increased. Our analysis of the temperature dependence of activation free energies uncovered an unusual entropic effect accompanying the reaction. The unique spatial structures around the Co active site at different temperatures influenced both the extent of charge transfer in the transition state and the arrangement of 3<em>d</em> orbital energy levels. We provided explanations consistent with the principles of thermodynamics and statistical physics. The insights gained at the atomic level have offered a fresh interpretation of the intricate long-range interplay between local chemical reactions and extensive chemical environments.</div></div>\",\"PeriodicalId\":9832,\"journal\":{\"name\":\"Chinese Journal of Catalysis\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":15.7000,\"publicationDate\":\"2024-10-01\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Chinese Journal of Catalysis\",\"FirstCategoryId\":\"92\",\"ListUrlMain\":\"https://www.sciencedirect.com/science/article/pii/S1872206724601166\",\"RegionNum\":1,\"RegionCategory\":\"化学\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q1\",\"JCRName\":\"CHEMISTRY, APPLIED\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chinese Journal of Catalysis","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1872206724601166","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, APPLIED","Score":null,"Total":0}
引用次数: 0
摘要
烷烃脱氢反应中的 C-H 键活化是决定反应速率的关键步骤。为了解熵的影响,我们在不同温度下对 Co@BEA 沸石上的乙烷脱氢反应进行了ab initio 静态和分子动力学自由能模拟。AIMD 模拟显示,随着温度的升高,自由能垒急剧下降。我们对活化自由能的温度依赖性进行了分析,发现了伴随反应发生的不寻常的熵效应。在不同温度下,Co 活性位点周围独特的空间结构既影响了过渡态中电荷转移的程度,也影响了 3d 轨道能级的排列。我们提供了符合热力学和统计物理学原理的解释。在原子水平上获得的见解为局部化学反应和广泛化学环境之间错综复杂的长程相互作用提供了全新的解释。
Ab initio molecular dynamics simulation reveals the influence of entropy effect on Co@BEA zeolite-catalyzed dehydrogenation of ethane
The C–H bond activation in alkane dehydrogenation reactions is a key step in determining the reaction rate. To understand the impact of entropy, we performed ab initio static and molecular dynamics free energy simulations of ethane dehydrogenation over Co@BEA zeolite at different temperatures. AIMD simulations showed that a sharp decrease in free energy barrier as temperature increased. Our analysis of the temperature dependence of activation free energies uncovered an unusual entropic effect accompanying the reaction. The unique spatial structures around the Co active site at different temperatures influenced both the extent of charge transfer in the transition state and the arrangement of 3d orbital energy levels. We provided explanations consistent with the principles of thermodynamics and statistical physics. The insights gained at the atomic level have offered a fresh interpretation of the intricate long-range interplay between local chemical reactions and extensive chemical environments.
期刊介绍:
The journal covers a broad scope, encompassing new trends in catalysis for applications in energy production, environmental protection, and the preparation of materials, petroleum chemicals, and fine chemicals. It explores the scientific foundation for preparing and activating catalysts of commercial interest, emphasizing representative models.The focus includes spectroscopic methods for structural characterization, especially in situ techniques, as well as new theoretical methods with practical impact in catalysis and catalytic reactions.The journal delves into the relationship between homogeneous and heterogeneous catalysis and includes theoretical studies on the structure and reactivity of catalysts.Additionally, contributions on photocatalysis, biocatalysis, surface science, and catalysis-related chemical kinetics are welcomed.