Shi Yue, Li Hong, Tsunematsu Hirofumi, Ozeki Harumi, Kano Kimiko, Yamamoto Eisuke, Kobayashi Makoto, Abe Hiroya, Chen Chun-Wei, Osada Minoru
Institute of Materials and Systems for Sustainability (IMaSS) & Department of Materials Chemistry, Nagoya University, Nagoya, 464-8601, Japan.
Joining and Welding Research Institute, Osaka University, Osaka, 567-0047, Japan.
Small. 2024 Sep;20(36):e2403915. doi: 10.1002/smll.202403915. Epub 2024 Jul 7.
In 2D materials, a key engineering challenge is the mass production of large-area thin films without sacrificing their uniform 2D nature and unique properties. Here, it is demonstrated that a simple fluid phenomenon of water/alcohol solvents can become a sophisticated tool for self-assembly and designing organized structures of 2D nanosheets on a water surface. In situ, surface characterizations show that water/alcohol droplets of 2D nanosheets with cationic surfactants exhibit spontaneous spreading of large uniform monolayers within 10 s. Facile transfer of the monolayers onto solid or flexible substrates results in high-quality mono- and multilayer films with high coverages (>95%) and homogeneous electronic/optical properties. This spontaneous spreading is quite general and can be applied to various 2D nanosheets, including metal oxides, graphene oxide, h-BN, MoS, and transition metal carbides, enabling on-demand smart manufacture of large-size (>4 inchϕ) 2D nanofilms and free-standing membranes.
在二维材料中，一个关键的工程挑战是在不牺牲其均匀二维特性和独特性能的前提下，大规模生产大面积薄膜。在此，研究表明水/醇类溶剂这一简单的流体现象可成为在水表面自组装和设计二维纳米片有序结构的精密工具。原位表面表征显示，带有阳离子表面活性剂的二维纳米片的水/醇液滴在10秒内会自发铺展形成大面积均匀单层。将单层轻松转移到固体或柔性基板上可得到高质量的单层和多层薄膜，其覆盖率高（>95%）且具有均匀的电子/光学特性。这种自发铺展具有普遍性，可应用于各种二维纳米片，包括金属氧化物、氧化石墨烯、h-BN、MoS以及过渡金属碳化物，从而能够按需智能制造大尺寸（>4英寸ϕ）二维纳米薄膜和独立膜。
