Three-Fold Enhancement of In-Plane Thermal Conductivity of Borophene through Metallic Atom Intercalation

作者：Yanxiao Hu, Yan Yin, Shichang Li, Hangbo Zhou, Dengfeng Li, Gang Zhang · 发表于：Nano Letters · 年份：2020 · DOI：10.1021/acs.nanolett.0c03135 · 被引用次数：50 · 研究领域：Thermal properties of materials、Boron and Carbon Nanomaterials Research、Machine Learning in Materials Science

We studied the thermal conductivity of Al-intercalated bilayer δ 4 borophene sheet by solving phonon Boltzmann transport equation based on density functional theory. Although the overall atomic density of Al-intercalated borophene is larger than that of δ 4 borophene, it possesses significant enhancement in in-plane thermal conductivity. With metallic atom intercalation, the armchair-direction thermal conductivity increases from 53.8 to 160.2 W m –1 K –1 and that along the zigzag direction increases from 115.7 to 157.2 W m –1 K –1 . This pronounced enhancement is attributed to the bunching of the acoustic branches in the Al-intercalated borophene, which decreases the phase space for the high frequency three acoustic phonon scattering processes. In addition to the pronounced increased thermal conductivity, the Al-intercalation also tunes the in-plane anisotropy. This study illustrates the importance of metallic atom intercalation in the in-plane thermal conductivity of 2D van der Waals materials and also has practical implications for fields ranging from thermal management to thermoelectrics design.