Self-Assembly of Thiourea-Crosslinked Graphene Oxide Framework Membranes toward Separation of Small Molecules
Self-Assembly of Thiourea-Crosslinked Graphene Oxide Framework Membranes toward Separation of Small Molecules
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硫脲交联氧化石墨烯骨架膜的自组装用于小分子的分离
DOI：
10.1002/adma.201705775
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发表时间：
2018
影响因子：
29.4
通讯作者：
Yuhan Sun
中科院分区：
文献类型：
--
作者：
Jingjing Yang;Dian Gong;Guihua Li;Gaofeng Zeng;Qiyan Wang;Yelei Zhang;Guojuan Liu;Ping Wu;Evgeny Vovk;Zheng Peng;Xiaohong Zhou;Yong Yang;Zhi Liu;Yuhan Sun
氧化石墨烯（GO）膜的机械强度差，由弱的层间相互作用引起的，对任何实际应用提出了关键的挑战。此外，堆叠的GO膜的固有但大尺寸的2D通道导致对小分子的低选择性。为了解决机械强度和2D通道尺寸控制问题，通过简单的水热自组装合成开发了多孔陶瓷上的硫脲共价连接的氧化石墨烯框架（TU-GOF）膜。通过这种策略，硫脲桥连的GO通过经由NH 2和/或NH3 SH与NH3 OH的脱水缩合反应以及NH3 NH 2与NH3 OH的亲核加成反应周期性地层压，由于共价TU-连接的小尺寸和脱氧过程，导致狭窄且结构良好限定的2D通道。所得到的TU-GOF/陶瓷复合膜具有对小物种的优异筛分能力，从而在气体、溶剂和盐水分离中具有高的氢选择性渗透率和对甲醇和小离子的几乎完全排斥。此外，在GO/载体和GO/GO界面处形成的共价键赋予复合膜显著增强的稳定性。
The poor mechanical strength of graphene oxide (GO) membranes, caused by the weak interlamellar interactions, poses a critical challenge for any practical application. In addition, intrinsic but large‐sized 2D channels of stacked GO membranes lead to low selectivity for small molecules. To address the mechanical strength and 2D channel size control, thiourea covalent‐linked graphene oxide framework (TU‐GOF) membranes on porous ceramics are developed through a facile hydrothermal self‐assembly synthesis. With this strategy, thiourea‐bridged GO laminates periodically through the dehydration condensation reactions via NH2and/or SH with OCOH as well as the nucleophilic addition reactions of NH2to COC, leading to narrowed and structurally well‐defined 2D channels due to the small dimension of the covalent TU‐link and the deoxygenated processes. The resultant TU‐GOF/ceramic composite membranes feature excellent sieving capabilities for small species, leading to high hydrogen permselectivities and nearly complete rejections for methanol and small ions in gas, solvent, and saline water separations. Moreover, the covalent bonding formed at the GO/support and GO/GO interfaces endows the composite membrane with significantly enhanced stability.