Hong Yang, Kretchmer Joshua S
School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332, USA.
J Chem Phys. 2022 Apr 28;156(16):164703. doi: 10.1063/5.0079462.
Similar to graphene, diamane is a single layer of diamond that has been investigated in recent years due to its peculiar mechanical, thermal, and electronic properties. Motivated by earlier work that showed an exceptionally high intra-plane thermal conductivity in diamane, in this work, we investigate the interfacial thermal resistance (R) between graphene and diamane using non-equilibrium classical molecular dynamics simulations. The calculated R for a pristine graphene and AB-stacked diamane at room temperature is 1.89 × 10 K m/W, which is comparable to other common graphene/semi-conductor bilayers. These results are understood in terms of the overlap of the phonon density of states between the graphene and diamane layers. We further explore the impact of stacking pattern, system temperature, coupling strength, in-plane tensile strain, and hydrogenation ratio on R. Intriguingly, we find that unlike single layer diamane, where the intra-plane thermal conductively is reduced by ∼50% under 5% strain, the inter-plane thermal conductance of the graphene-diamane bilayer is enhanced by ∼50% under 8% strain. The difference is caused by the opposite behavior between the inter- and intra-layer conductances as phonon relaxation time is decreased. The high intra-plane thermal conductivity and low inter-plane thermal resistance shows the high potential of using graphene-diamane heterostructures in electronic applications.
与石墨烯类似,二胺是单层金刚石,近年来因其独特的机械、热学和电学性质而受到研究。受早期研究表明二胺具有极高的面内热导率的启发,在本工作中,我们使用非平衡经典分子动力学模拟研究了石墨烯与二胺之间的界面热阻(R)。在室温下,计算得到的原始石墨烯与AB堆叠二胺的R为1.89×10 K·m/W,这与其他常见的石墨烯/半导体双层相当。这些结果可以通过石墨烯层和二胺层之间声子态密度的重叠来理解。我们进一步探讨了堆叠模式、系统温度、耦合强度、面内拉伸应变和氢化率对R的影响。有趣的是,我们发现与单层二胺不同,单层二胺在5%应变下面内热导率降低约50%,而石墨烯-二胺双层在8%应变下面内热导增强约50%。这种差异是由于声子弛豫时间减少时层间和层内电导率的相反行为引起的。高的面内热导率和低的面内热阻表明在电子应用中使用石墨烯-二胺异质结构具有很大潜力。