An Analysis of Shear-Dependent Mechanochemical Reaction Kinetics

IF 2.9 3区 工程技术 Q2 ENGINEERING, CHEMICAL Tribology Letters Pub Date : 2024-06-12 DOI:10.1007/s11249-024-01879-9
Resham Rana, Nicholas Hopper, François Sidoroff, Juliette Cayer-Barrioz, Denis Mazuyer, Wilfred T. Tysoe
{"title":"An Analysis of Shear-Dependent Mechanochemical Reaction Kinetics","authors":"Resham Rana,&nbsp;Nicholas Hopper,&nbsp;François Sidoroff,&nbsp;Juliette Cayer-Barrioz,&nbsp;Denis Mazuyer,&nbsp;Wilfred T. Tysoe","doi":"10.1007/s11249-024-01879-9","DOIUrl":null,"url":null,"abstract":"<div><p>This paper shows how the effect of combined normal and shear stresses on the rates of tribochemical reactions can be calculated using Evans-Polanyi (E-P) perturbation theory. The E-P approach is based on transition-state theory, where the rate of reaction is taken to be proportional to the concentration of activated complex. The equilibrium constant depends on the molar Gibbs free energy change between the initial- and transition-states, which, in turn, depends on the stresses. E-P theory has been used previously to successfully calculate the effects of normal stresses on reaction rates. In this case, ln(Rate) varies linearly with stress with a slope given by an activation volume, which broadly corresponds to the volume difference between the reactant and activated complex. An advantage of E-P theory is that it can calculate the influence of several perturbations, for example, the normal stress dependence of the shear stress during sliding. In this paper, E-P theory is used to calculate shear-induced, tribochemical reaction rates. The results depend on four elementary activation volumes for different contributions to the Gibbs free energy: two of them due to normal and shear stresses for sliding over the surface and two more for the surface reaction. The results of the calculations show that there is a linear dependence of ln(Rate) on the normal stress but that the coefficient of proportionality between the ln(Rate) and the normal stress now has contributions from all elementary-step activation volumes. Counterintuitively, the analysis predicts that the ln(Rate)-normal stress evolution tends, at zero normal stress, to an asymptotic rate constant that depends on sliding velocity and differs from the thermal reaction rate. The theoretical prediction is verified for the shear-induced decomposition of ethyl thiolate species adsorbed on a Cu(100) single crystal substrate that decomposes by C‒S bond cleavage. The theoretical analyses show that tribochemical reactions can be influenced by either just normal stresses or by a combination of normal and shear stresses, but that the latter effect is much greater. Finally, it is predicted that there should be a linear relationship between the activation energy and the logarithm of the pre-exponential factor of the asymptotic rate constant.</p><h3>Graphical Abstract</h3>\n<div><figure><div><div><picture><source><img></source></picture></div></div></figure></div></div>","PeriodicalId":806,"journal":{"name":"Tribology Letters","volume":null,"pages":null},"PeriodicalIF":2.9000,"publicationDate":"2024-06-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Tribology Letters","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s11249-024-01879-9","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENGINEERING, CHEMICAL","Score":null,"Total":0}
引用次数: 0

Abstract

This paper shows how the effect of combined normal and shear stresses on the rates of tribochemical reactions can be calculated using Evans-Polanyi (E-P) perturbation theory. The E-P approach is based on transition-state theory, where the rate of reaction is taken to be proportional to the concentration of activated complex. The equilibrium constant depends on the molar Gibbs free energy change between the initial- and transition-states, which, in turn, depends on the stresses. E-P theory has been used previously to successfully calculate the effects of normal stresses on reaction rates. In this case, ln(Rate) varies linearly with stress with a slope given by an activation volume, which broadly corresponds to the volume difference between the reactant and activated complex. An advantage of E-P theory is that it can calculate the influence of several perturbations, for example, the normal stress dependence of the shear stress during sliding. In this paper, E-P theory is used to calculate shear-induced, tribochemical reaction rates. The results depend on four elementary activation volumes for different contributions to the Gibbs free energy: two of them due to normal and shear stresses for sliding over the surface and two more for the surface reaction. The results of the calculations show that there is a linear dependence of ln(Rate) on the normal stress but that the coefficient of proportionality between the ln(Rate) and the normal stress now has contributions from all elementary-step activation volumes. Counterintuitively, the analysis predicts that the ln(Rate)-normal stress evolution tends, at zero normal stress, to an asymptotic rate constant that depends on sliding velocity and differs from the thermal reaction rate. The theoretical prediction is verified for the shear-induced decomposition of ethyl thiolate species adsorbed on a Cu(100) single crystal substrate that decomposes by C‒S bond cleavage. The theoretical analyses show that tribochemical reactions can be influenced by either just normal stresses or by a combination of normal and shear stresses, but that the latter effect is much greater. Finally, it is predicted that there should be a linear relationship between the activation energy and the logarithm of the pre-exponential factor of the asymptotic rate constant.

Graphical Abstract

Abstract Image

查看原文
分享 分享
微信好友 朋友圈 QQ好友 复制链接
本刊更多论文
依赖剪切力的机械化学反应动力学分析
本文展示了如何利用埃文斯-波兰尼(E-P)扰动理论计算法向应力和剪切应力对摩擦化学反应速率的影响。E-P 方法基于过渡态理论,反应速率与活化复合物的浓度成正比。平衡常数取决于初始状态和过渡状态之间的摩尔吉布斯自由能变化,而这又取决于应力。E-P 理论曾用于成功计算法向应力对反应速率的影响。在这种情况下,ln(速率)随应力呈线性变化,斜率由活化体积决定,活化体积大致相当于反应物和活化复合物之间的体积差。E-P 理论的一个优点是可以计算多种扰动的影响,例如滑动过程中剪应力与法向应力的关系。本文采用 E-P 理论计算剪切力引起的摩擦化学反应速率。计算结果取决于四个基本活化量对吉布斯自由能的不同贡献:其中两个是由于表面滑动时的法向应力和剪切应力引起的,另外两个是由于表面反应引起的。计算结果显示,ln(Rate) 与法向应力呈线性关系,但现在 ln(Rate)与法向应力之间的比例系数来自所有基本活化量。与直觉相反的是,分析预测 ln(Rate)-法向应力演变在法向应力为零时趋向于一个渐近速率常数,该速率常数取决于滑动速度,并与热反应速率不同。这一理论预测在吸附在 Cu(100)单晶基底上的硫醇酸乙酯物种的剪切诱导分解中得到了验证,该物种通过 C-S 键裂解而分解。理论分析表明,摩擦化学反应既可能只受法向应力的影响,也可能受法向应力和剪切应力的共同影响,但后者的影响要大得多。最后,根据预测,活化能与渐近速率常数的前指数因子的对数之间应存在线性关系。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 去求助
来源期刊
Tribology Letters
Tribology Letters 工程技术-工程:化工
CiteScore
5.30
自引率
9.40%
发文量
116
审稿时长
2.5 months
期刊介绍: Tribology Letters is devoted to the development of the science of tribology and its applications, particularly focusing on publishing high-quality papers at the forefront of tribological science and that address the fundamentals of friction, lubrication, wear, or adhesion. The journal facilitates communication and exchange of seminal ideas among thousands of practitioners who are engaged worldwide in the pursuit of tribology-based science and technology.
期刊最新文献
Wear Mechanism and Wear Debris Characterization of ULWPE in Multidirectional Motion Cobalt- and Chromium-Oxide-Based Coatings: Thermally Spraying a Glaze Layer Visualization of Structural Deformation of Polymer Additives in Oil Under High Shear Flow Influence of Variable-Depth Groove Texture on the Friction and Wear Performance of GCr15–SiC Friction Pairs Under Water Lubrication The Flow of Lubricant as a Mist in the Piston Assembly and Crankcase of a Fired Gasoline Engine: The Effect of Viscosity Modifier and the Link to Lubricant Degradation
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
现在去查看 取消
×
提示
确定
0
微信
客服QQ
Book学术公众号 扫码关注我们
反馈
×
意见反馈
请填写您的意见或建议
请填写您的手机或邮箱
已复制链接
已复制链接
快去分享给好友吧!
我知道了
×
扫码分享
扫码分享
Book学术官方微信
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术
文献互助 智能选刊 最新文献 互助须知 联系我们:info@booksci.cn
Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。
Copyright © 2023 Book学术 All rights reserved.
ghs 京公网安备 11010802042870号 京ICP备2023020795号-1