Heijmans Koen, Pathak Amar Deep, Solano-López Pablo, Giordano Domenico, Nedea Silvia, Smeulders David
Energy Technology, Department of Mechanical Engineering, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands.
Departmento de Fisica Aplicada, ETSIAE, Universidad Politécnica de Madrid, 28040 Madrid, Spain.
Nanomaterials (Basel). 2019 Apr 26;9(5):663. doi: 10.3390/nano9050663.
The interface of two solids in contact introduces a thermal boundary resistance (TBR), which is challenging to measure from experiments. Besides, if the interface is reactive, it can form an intermediate recrystallized or amorphous region, and extra influencing phenomena are introduced. Reactive force field Molecular Dynamics (ReaxFF MD) is used to study these interfacial phenomena at the (non-)reactive interface. The non-reactive interfaces are compared using a phenomenological theory (PT), predicting the temperature discontinuity at the interface. By connecting ReaxFF MD and PT we confirm a continuous temperature profile for the homogeneous non-reactive interface and a temperature jump in case of the heterogeneous non-reactive interface. ReaxFF MD is further used to understand the effect of chemical activity of two solids in contact. The selected Si/SiO 2 materials showed that the TBR of the reacted interface is two times larger than the non-reactive, going from 1 . 65 × 10 - 9 to 3 . 38 × 10 - 9 m 2 K/W. This is linked to the formation of an intermediate amorphous layer induced by heating, which remains stable when the system is cooled again. This provides the possibility to design multi-layered structures with a desired TBR.
两个相互接触的固体界面会引入热边界电阻（TBR），而通过实验测量该电阻具有挑战性。此外，如果界面具有反应活性，它会形成一个中间再结晶或非晶区域，并引入额外的影响现象。反应力场分子动力学（ReaxFF MD）用于研究（非）反应性界面处的这些界面现象。使用唯象理论（PT）对非反应性界面进行比较，预测界面处的温度不连续性。通过将ReaxFF MD和PT相结合，我们证实了均匀非反应性界面的温度分布是连续的，而异质非反应性界面则存在温度跃变。ReaxFF MD还用于理解两个相互接触的固体的化学活性的影响。所选的Si/SiO₂材料表明，反应界面的TBR是非反应界面的两倍，从1.65×10⁻⁹增加到3.38×10⁻⁹ m²K/W。这与加热诱导形成的中间非晶层有关，当系统再次冷却时，该非晶层保持稳定。这为设计具有所需TBR的多层结构提供了可能性。
