Muthaiah Rajmohan, Tarannum Fatema, Annam Roshan Sameer, Nayal Avinash Singh, Danayat Swapneel, Garg Jivtesh
School of Aerospace and Mechanical Engineering, University of Oklahoma Norman OK-73019 USA
RSC Adv. 2020 Nov 23;10(70):42628-42632. doi: 10.1039/d0ra08444a.
In this work, we report a high thermal conductivity () of 162 W m K and 52 W m K at room temperature, along the directions perpendicular and parallel to the -axis, respectively, of bulk hexagonal BCP (h-BCP), using first-principles calculations. We systematically investigate elastic constants, phonon group velocities, phonon linewidths and mode thermal conductivity contributions of transverse acoustic (TA), longitudinal acoustic (LA) and optical phonons. Interestingly, optical phonons are found to make a large contribution of 30.1% to the overall along a direction perpendicular to the -axis at 300 K. BCP is also found to exhibit high thermal conductivity at nanometer length scales. At 300 K, a high value of ∼47 W m K is computed for h-BCP at a nanometer length scale of 50 nm, providing avenues for achieving efficient nanoscale heat transfer.
在这项工作中，我们通过第一性原理计算报告了块状六方BCP（h-BCP）在室温下沿垂直于和平行于c轴方向的高导热率，分别为162 W m⁻¹ K⁻¹和52 W m⁻¹ K⁻¹。我们系统地研究了弹性常数、声子群速度、声子线宽以及横向声学（TA）、纵向声学（LA）和光学声子的模式热导率贡献。有趣的是，在300 K时，发现光学声子在垂直于c轴的方向上对整体热导率的贡献高达30.1%。还发现BCP在纳米长度尺度上也表现出高导热率。在300 K时，对于50 nm纳米长度尺度的h-BCP，计算出的高热导率值约为47 W m⁻¹ K⁻¹，为实现高效的纳米级热传递提供了途径。
