On Stress-Induced Tribochemical Reaction Rates
On Stress-Induced Tribochemical Reaction Rates
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DOI：
10.1007/s11249-017-0832-x
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发表时间：
2017-03
影响因子：
3.2
通讯作者：
W. Tysoe
中科院分区：
文献类型：
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作者：
W. Tysoe
最近的一些实验已经证明，法向应力和剪切应力能够加速表面上的吸附物的化学反应速率，产生与力的反应速率的近似指数增加。看来，这种机械化学反应在摩擦化学和润滑剂添加剂的抗磨或减摩膜的形成中起着核心作用。因此，总结可用于分析此类摩擦化学数据的理论是适当的。该模型与用于分析滑动摩擦的普朗特/汤姆林森模型有很强的相似性。研究发现，化学反应的力依赖活化势垒随温度的变化而变化。利用模型反应能量分布分析了活化势垒随力的线性变化，即所谓的Bell方程和二次依赖性，即所谓的哈蒙德效应，揭示了参数A和B对能量分布形状的依赖性。同时讨论了接触压力和滑动速度的影响。上述模型假定摩擦化学过程的正应力和剪应力与热反应坐标共面，并讨论了不满足这一条件的影响。最后，利用这些模型分析了现有的含氧功能化石墨烯与二烷基二硫代磷酸锌的摩擦化学反应结果。
A number of recent experiments have demonstrated that normal and shear stresses are able to accelerate the rates of chemical reactions of adsorbates on surfaces, yielding an approximately exponential increase in reaction rate with force. It seems that such mechanochemical reactions play a central role in tribochemistry and the consequent formation of anti-wear or friction-reducing films from lubricant additives. It is thus appropriate to summarize the theories that can be used to analyse such tribochemical data. The models have a strong parallel with those used to analyse sliding friction, the Prandtl/Tomlinson model. It is found that the force-dependent activation barrier for chemical reactions varies as. The linear variation in activation barrier with force, the so-called Bell equation, and the quadratic dependence, the so-called Hammond effect, are analysed using model reaction energy profiles, which reveal a dependence of the parametersAandBon the shape of the energy profile. The influence of contact pressure and sliding velocity is also discussed. The above models assume that the normal and shear stresses are coplanar with the thermal reaction coordinate for the tribochemical processes, and the effects of this not being the case are also discussed. Finally, the existing results of tribochemical reactions of oxygen-functionalized graphene and zinc dialkyl dithiophosphates are also analysed using these models.