Zhao Jinlai, Zhu Jiajie, Cao Rui, Wang Huide, Guo Zhinan, Sang David K, Tang Jiaoning, Fan Dianyuan, Li Jianqing, Zhang Han
Faculty of Information Technology, Macau University of Science and Technology, Avenida Wai Long, Taipa, Macau, 999078, PR China.
Shenzhen Engineering Laboratory of Phosphorene and Optoelectronics, International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology, Engineering Technology Research Center for 2D Material Information Function Devices and Systems of Guangdong Province, Institute of Microscale Optoelectronics (IMO), Shenzhen University, Shenzhen, 518060, PR China.
Nat Commun. 2019 Sep 6;10(1):4062. doi: 10.1038/s41467-019-11937-9.
The growth and wetting of water on two-dimensional(2D) materials are important to understand the development of 2D material based electronic, optoelectronic, and nanomechanical devices. Here, we visualize the liquefaction processes of water on the surface of graphene, MoS and black phosphorus (BP) via optical microscopy. We show that the shape of the water droplets forming on the surface of BP, which is anisotropic, is elliptical. In contrast, droplets are rounded when they form on the surface of graphene or MoS, which do not possess orthometric anisotropy. Molecular simulations show that the anisotropic liquefaction process of water on the surface of BP is attributed to the different binding energies of HO molecules on BP along the armchair and zigzag directions. The results not only reveal the anisotropic nature of water liquefaction on the BP surface but also provide a way for fast and nondestructive determination of the crystalline orientation of BP.
水在二维（2D）材料上的生长和润湿性对于理解基于二维材料的电子、光电子和纳米机械设备的发展至关重要。在此，我们通过光学显微镜观察了水在石墨烯、二硫化钼（MoS）和黑磷（BP）表面的液化过程。我们发现，在具有各向异性的BP表面形成的水滴形状为椭圆形。相比之下，在不具有正交各向异性的石墨烯或MoS表面形成的水滴则是圆形的。分子模拟表明，水在BP表面的各向异性液化过程归因于HO分子在BP表面沿扶手椅方向和锯齿方向的结合能不同。这些结果不仅揭示了BP表面水液化的各向异性本质，还为快速无损确定BP的晶体取向提供了一种方法。
