Song Jieren, Xu Zhonghai, He Xiaodong, Cai Chaocan, Bai Yujiao, Miao Linlin, Wang Rongguo
National Key Laboratory of Science and Technology on Advanced Composites in Special Environments, Harbin Institute of Technology, Harbin 150080, P. R. China.
Phys Chem Chem Phys. 2020 May 28;22(20):11537-11545. doi: 10.1039/d0cp01727b. Epub 2020 May 12.
In-plane heterojunctions, obtained by seamlessly joining two or more nanoribbon edges of isolated two-dimensional atomic crystals such as graphene and hexagonal boron nitride, are emerging as nanomaterials for the development of future multifunctional devices. The thermal transport behavior at the interface of these heterojunctions plays a pivotal role in determining their functional performance. Using molecular dynamics simulations, the interfacial thermal conductance of graphene/hexagonal boron nitride (GE/BN) in-plane heterojunctions was investigated. The GE/BN heterostructure has a remarkably high interfacial thermal conductance, and thermal rectification occurs at the interface. The results also show that the interfacial thermal conductance is effectively modulated by strain and defect engineering. The atomic defect location can affect the phonon transmission at the interface. Interestingly, compared with the nitrogen doping effect, the boron doping defect can more effectively facilitate vibrational coupling at the interface in the graphene sheet. Stress distribution and vibrational spectral analyses are performed to elucidate the thermal transport mechanism. The results of this study may provide a foundation for future research attempting to manipulate the interfacial thermal conductance in other two-dimensional heterostructures.
通过无缝连接石墨烯和六方氮化硼等孤立二维原子晶体的两个或多个纳米带边缘获得的面内异质结，正作为未来多功能器件开发的纳米材料而兴起。这些异质结界面处的热输运行为在决定其功能性能方面起着关键作用。利用分子动力学模拟，研究了石墨烯/六方氮化硼（GE/BN）面内异质结的界面热导率。GE/BN异质结构具有非常高的界面热导率，并且在界面处发生热整流。结果还表明，界面热导率可通过应变和缺陷工程有效地进行调制。原子缺陷位置会影响界面处的声子传输。有趣的是，与氮掺杂效应相比，硼掺杂缺陷能更有效地促进石墨烯片中界面处的振动耦合。进行了应力分布和振动光谱分析以阐明热输运机制。本研究结果可能为未来试图操纵其他二维异质结构中界面热导率的研究提供基础。
