Huang Yubin, Spiece Jean, Parker Tetiana, Lee Asaph, Gogotsi Yury, Gehring Pascal
Institute of Condensed Matter and Nanosciences, Université catholique de Louvain (UCLouvain), 1348 Louvain-la-Neuve, Belgium.
A. J. Drexel Nanomaterials Institute and Department of Materials Science and Engineering, Drexel University, Philadelphia, Pennsylvania 19104, United States.
ACS Nano. 2024 Nov 26;18(47):32491-32497. doi: 10.1021/acsnano.4c08189. Epub 2024 Nov 17.
The high electrical conductivity and good chemical stability of MXenes offer hopes for their use in many applications, such as wearable electronics, energy storage, and electromagnetic interference shielding. While their optical, electronic, and electrochemical properties have been widely studied, information on the thermal properties of MXenes is scarce. In this study, we investigate the heat transport properties of TiCT MXene single flakes using scanning thermal microscopy and find exceptionally low anisotropic thermal conductivities within the TiCT flakes, leading to an effective thermal conductivity of 0.78 ± 0.21 W m K. This observation is in stark contrast to the predictions of the Wiedemann-Franz law, as the estimated Lorenz number is only 0.25 of the classical value. Due to the combination of low thermal conductivity and low emissivity of TiCT, the heat loss from it is 2 orders of magnitude smaller than that from common metals. Our study explores the heat transport mechanisms of MXenes and highlights a promising approach for developing thermal insulation, two-dimensional thermoelectric, or infrared stealth materials.
MXenes的高电导率和良好的化学稳定性为其在许多应用中的使用带来了希望，如可穿戴电子产品、能量存储和电磁干扰屏蔽。虽然它们的光学、电子和电化学性质已得到广泛研究，但关于MXenes热性质的信息却很少。在本研究中，我们使用扫描热显微镜研究了TiCT MXene单薄片的热输运性质，发现TiCT薄片内的各向异性热导率极低，导致有效热导率为0.78±0.21 W m⁻¹ K⁻¹。这一观察结果与维德曼-弗兰兹定律的预测形成鲜明对比，因为估计的洛伦兹数仅为经典值的0.25。由于TiCT的低导热率和低发射率相结合，其热损失比普通金属小两个数量级。我们的研究探索了MXenes的热输运机制，并突出了一种开发隔热、二维热电或红外隐身材料的有前景的方法。
