Zhang Chenxin, Sun Jie, Shen Yiheng, Kang Wei, Wang Qian
School of Materials Science and Engineering, Center for Applied Physics and Technology, BKL-MEMD, Peking University, Beijing 100871, China.
Center for Applied Physics and Technology, College of Engineering, Peking University, Beijing 100871, China.
J Phys Chem Lett. 2022 Jun 30;13(25):5734-5741. doi: 10.1021/acs.jpclett.2c01531. Epub 2022 Jun 17.
Motivated by the recent synthesis of penta-NiN, a new two-dimensional (2D) planar material entirely composed of pentagons [ 2021, 15, 13539], we study its thermal transport properties based on first-principles calculations and solving the Boltzmann transport equation within the self-consistent phonon theory and four-phonon scattering formalism. We find that the intrinsic lattice thermal conductivity of penta-NiN is 11.67 W/mK at room temperature, which is reduced by 89.32% as compared to the value obtained by only considering three-phonon scattering processes. More interestingly, different from the general response of thermal conductivity to external strain in most 2D materials, an oscillatory decrease of the thermal conductivity with increasing biaxial tensile strain is observed, which can be attributed to the renormalization of vibrational frequencies and the nonmonotonic variation of phonon scattering rates. This work provides an accurate intrinsic thermal conductivity of penta-NiN and elucidates the effects of the strain-tuned vibrational modes and phonon band gap on the four-phonon scattering processes, shedding light on a better understanding of the physical mechanisms of thermal transport properties in 2D pentagon-based materials.
受近期合成的全由五边形组成的新型二维平面材料五氮化镍（2021年，15卷，13539页）的启发，我们基于第一性原理计算并在自洽声子理论和四声子散射形式体系内求解玻尔兹曼输运方程，研究了其热输运性质。我们发现，五氮化镍在室温下的本征晶格热导率为11.67W/(m·K)，与仅考虑三声子散射过程时得到的值相比降低了89.32%。更有趣的是，与大多数二维材料中热导率对外加应变的一般响应不同，我们观察到随着双轴拉伸应变增加热导率呈振荡下降，这可归因于振动频率的重整化和声子散射率的非单调变化。这项工作给出了五氮化镍准确的本征热导率，并阐明了应变调谐的振动模式和声子带隙对四声子散射过程的影响，有助于更好地理解基于二维五边形材料的热输运性质的物理机制。
