Abstract Ion sieving is of great importance in a variety of applications, such as water desalination/purification, biomedical engineering and so on. The currently available techniques, based on ion size sieving by constructing membranes with nanochannels and nanopores, are still not able to achieve precise sieving of mono-/multi-valent metal ions. Here, we report on the fabrication of graphene-based membranes by constructing uniform two-dimensional (2D) nanochannels with effective channel heights of ~ 8 A for precise and efficient sieving of mono-/multi-valent metal ions. Our membranes with uniform 2D nanochannels are built using facilely reduced graphene oxide (FRGO) nanosheets, which are controllably fabricated by avoiding the corrugation of graphene oxide (GO) nanosheets and controlling the content of oxidation groups during the reduction process. We illustrate the ability of precise sieving of mono-/multi-valent metal ions afforded by this technique by fabricating FRGO membranes with uniform 2D nanochannels, and demonstrate the excellent repeatability and long-term stability of FRGO membranes for sieving of mono-/multi-valent metal ions.

中文翻译：

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具有均匀二维纳米通道的基于石墨烯的膜，用于精确筛分单价/多价金属离子

摘要 离子筛分在海水淡化/净化、生物医学工程等多种应用中具有重要意义。目前可用的技术，基于通过构建具有纳米通道和纳米孔的膜来进行离子大小筛分，仍然无法实现单价/多价金属离子的精确筛分。在这里，我们报告了通过构建均匀的二维 (2D) 纳米通道来制造石墨烯基膜，其有效通道高度为 ~ 8 A，用于精确有效地筛分单价/多价金属离子。我们具有均匀 2D 纳米通道的膜是使用易还原的氧化石墨烯 (FRGO) 纳米片构建的，通过避免氧化石墨烯（GO）纳米片的波纹和在还原过程中控制氧化基团的含量来可控地制造。我们通过制造具有均匀 2D 纳米通道的 FRGO 膜来说明该技术提供的单价/多价金属离子的精确筛分能力，并证明了 FRGO 膜在筛分单价/多价金属离子方面具有出色的可重复性和长期稳定性。价金属离子。