超薄石墨烯基多孔分离膜的构筑及其分离性能研究

Pressure-driven separation membranes are the key technologies which are widely used in petrochemical, environment remediation, desalination, waste-water treatment, and energy et.al. industrial processes. The separation theory shows that the thinner the membrane, the higher the separation efficient is. However, when the thickness is reduced, the mechanical property and the selectivity of the membrane will be lost. It is still a challenge to prepare high efficient ultrathin separation membranes. In this project, based on the unique strong mechanical strength and chemical properties of graphene-based materials with atomic thick, large scale two-dimensional structures, we will use them (produced by both chemical vapor deposition and solution chemical exfoliation) to construct unique ultrathin porous graphene-based membranes for separation.The preparation method is similar to that we used before for ultrathin protein membranes and diamond-like carbon membranes by nanofibers, respectively. In order to achieve high separation performance graphene-based membranes, the layer number of graphene (or the thickness of the membranes), the channel structures, pore diameter, functional groups designation will be tuned in detail. The separation performances for different molecules, ions as well as nanoparticle will be investigated systematically, and summarize the optimized preparation parameters for the membranes, which can be used for separation molecules or particles from liquid system, respectively. The separation mechanism will be studied and explained deeply. Based on the results, prototype high performance graphene-based membranes will be developed for real membrane separation system. This study will extend the application of graphen-based materials into a new field of separation membranes.

压力驱动分离膜技术是目前石油化工,环境保护，海水淡化，污水处理和能源等工业过程中的关键技术。分离理论显示膜越薄，分离效率越高。但是降低膜厚会损失膜的机械性能和选择性。制备超薄高效分离膜还是一个挑战。基于石墨烯基材料优异的机械性能和原子级厚的宏观二维结构，本项目将继续利用我们以前通过纳米线构筑超薄蛋白质及类金刚石分离膜的方法来构筑石墨烯基超薄多孔分离膜。通过对石墨烯基分离膜厚度的控制、通道结构的调控、孔径调节、功能化设计、获得具有高选择性、高通量的石墨烯基超薄多孔分离膜。系统研究不同条件下制备的石墨烯基膜对不同分子、离子、纳米颗粒的分离特性，总结出可用于液体分离方面的多孔石墨烯基纳米分离膜的制备参数和工艺。揭示其分离机理，设计出超薄高效的石墨烯基分离膜实验原型系统。该研究具有一定的原创性，拓展了石墨烯基材料的应用范围，在分离膜领域具有重要的应用前景和科学意义。

高效压力驱动分离膜技术在化工,环境保护，海水淡化，污水处理和能源等工业过程中具有非常重要的应用。石墨烯及其他原子级厚二维层状材料具有很好的物理化学性能、表面结构以及表面性能等，有望应用于构筑高性能物质的传输并应用于分离膜。本项目利用溶液剥离法制备的氧化石墨烯、二硫化钼、二硫化钨以及过度族金属层状材料来构筑多孔薄膜。通过通道结构的构筑，孔径调节，官能团的选择等设计，并经简单的过滤获得具有高选择性、高通量分离特性的二维层状材料多孔分离膜.系统研究了其分离性能，并发现水在亲水性3nm的二维孔道中仍然遵循传统的粘滞流传输机理。该研究拓展了石墨烯基材料的应用范围，在分离膜领域具有现实的应用前景和科学意义。.另外在这些二维层状材料多孔分离膜也可以直接应用于无粘结剂的电极材料，本项目也构筑了多种基于二维层状材料的多孔柔性无粘结剂的高效电极材料。