Chen Shao-Nan, Liu Xu-Shan, Luo Rong-Hui, Xu En-Ze, Tian Jian-Guo, Liu Zhi-Bo
The Key Laboratory of Weak Light Nonlinear Photonics, Ministry of Education, School of Physics and Teda Applied Physics Institute, Nankai University, Tianjin 300071, China.
Renewable Energy Conversion and Storage Center, Nankai University, Tianjin 300071, China.
ACS Appl Mater Interfaces. 2022 May 18;14(19):22626-22633. doi: 10.1021/acsami.2c04253. Epub 2022 May 6.
Tuning the thermal properties of materials is considered to be of crucial significance for improving the performance of electronic devices. Along these lines, the development of van der Waals (vdW) heterostructures becomes an effective solution to affect the thermal transport mechanisms. However, vdW interactions usually block phonon transport, which leads to a reduction in thermal conductivity. In this work, we experimentally demonstrate a large enhancement in the thermal conductivity of a vdW heterostructure composed of few-layer hexagonal boron nitride (h-BN) and reduced graphene oxide (RGO). By controlling the reduction temperature of RGO and changing the thickness of h-BN, the thermal conductivity of the RGO is increased by nearly 18 times, namely, from 91 to 1685 W m K. Photothermal scanning imaging is used to reveal the changes in the heat transfer and temperature distribution of the h-BN/RGO heterostructure. Both photothermal scanning and Raman spectroscopy experiments show that the vdW interaction between h-BN and RGO can greatly increase the thermal conductivity of RGO, which is in contrast to the conventional understanding that vdW interaction reduces thermal conductivity. Our work paves the way for the manipulation of the thermal conductivity of two-dimensional (2D) heterostructures, which could be of great significance for future nanoelectronic circuits.
调节材料的热性能被认为对提高电子器件的性能至关重要。沿着这些思路，范德华（vdW）异质结构的发展成为影响热传输机制的有效解决方案。然而，范德华相互作用通常会阻碍声子传输，从而导致热导率降低。在这项工作中，我们通过实验证明了由少层六方氮化硼（h-BN）和还原氧化石墨烯（RGO）组成的范德华异质结构的热导率有大幅提高。通过控制RGO的还原温度并改变h-BN的厚度，RGO的热导率提高了近18倍，即从91 W m⁻¹ K⁻¹提高到1685 W m⁻¹ K⁻¹。光热扫描成像用于揭示h-BN/RGO异质结构的热传递和温度分布变化。光热扫描和拉曼光谱实验均表明，h-BN与RGO之间的范德华相互作用可大幅提高RGO的热导率，这与范德华相互作用会降低热导率的传统认识相反。我们的工作为二维（2D）异质结构热导率的调控铺平了道路，这对未来的纳米电子电路可能具有重要意义。
