Lu J, Persson I, Lind H, Palisaitis J, Li M, Li Y, Chen K, Zhou J, Du S, Chai Z, Huang Z, Hultman L, Eklund P, Rosen J, Huang Q, Persson P O Å
Thin Film Physics Division, Department of Physics, Chemistry and Biology (IFM), Linköping University SE-581 83 Linköping Sweden
Engineering Laboratory of Advanced Energy Materials (FiNE Lab.), Ningbo Institute of Industrial Technology, Chinese Academy of Sciences Ningbo Zhejiang 315201 China.
Nanoscale Adv. 2019 Jul 25;1(9):3680-3685. doi: 10.1039/c9na00324j. eCollection 2019 Sep 11.
MXenes are a rapidly growing family of 2D materials that exhibit a highly versatile structure and composition, allowing for significant tuning of the materials properties. These properties are, however, ultimately limited by the surface terminations, which are typically a mixture of species, including F and O that are inherent to the MXene processing. Other and robust terminations are lacking. Here, we apply high-resolution scanning transmission electron microscopy (STEM), corresponding image simulations and first-principles calculations to investigate the surface terminations on MXenes synthesized from MAX phases through Lewis acidic melts. The results show that atomic Cl terminates the synthesized MXenes, with mere residual presence of other termination species. Furthermore, STEM-electron energy loss spectroscopy (EELS) heating experiments show that the Cl terminations are stable up to 750 °C. Thus, we present an attractive new termination that widely expands the MXenes' functionalization space and enables new applications.
MXenes是一类快速发展的二维材料家族，具有高度通用的结构和组成，能够对材料性能进行显著调控。然而，这些性能最终受到表面端基的限制，表面端基通常是包括氟（F）和氧（O）在内的多种物质的混合物，这些物质是MXene制备过程中固有的。目前缺乏其他稳定的端基。在此，我们应用高分辨率扫描透射电子显微镜（STEM）、相应的图像模拟和第一性原理计算，来研究通过路易斯酸性熔体由MAX相合成的MXenes的表面端基。结果表明，原子氯终止了合成的MXenes表面，仅有其他端基物种的残留。此外，STEM-电子能量损失谱（EELS）加热实验表明，氯端基在高达750°C时都是稳定的。因此，我们提出了一种有吸引力的新型端基，它广泛扩展了MXenes的功能化空间，并开启了新的应用。
