大环超分子稳定化MoS2纳米片构筑二维层状分离膜及其限域传质机制

Two-dimensional lamellar nanocomposite membrane with confinement effect for mass transport shows great potential on enhancing separation performance, as well as solving the trade-off effect of permeability and selectivity. The stabilization and dispersion of two-dimensional laminar nanosheets and manipulation of the confined mass transfer channel during the membrane fabrication are the key scientific points for high performance membrane. This project proposed in situ modification of MoS2 nanosheets by supermolecular macrocyclic compounds with different cavity sizes and functional groups. The change of interlayer spacing and structure as well as fabrication of the membrane by self-assembly process are to be researched. The transportation channels in limited space of MoS2 nanosheets would be modified and constructed by size matching and molecular recognition of supramolecular cavity aiming at highly selective separation and efficient permeation of target components and solvent molecules, respectively. The transfer mechanism of different solvent molecules in the hydrophilic or hydrophobic cavity as well as within the two-dimensional confined channel would be investigated. The correlation rules between the microstructure parameters of the membrane surface and the separation performances, stability and antifouling property would be illustrated. This proposal would provide a theoretical guidance and fundamental basis for efficiently separating complex organic mixture in practical applications. Also, the project would open up a new route for utilization of other two-dimensional materials in membrane field.

具有限域传质效应的二维纳米片层基复合膜对于提升膜的分离性能、突破渗透性和选择性的博弈效应显示巨大的潜力。本项目围绕二维层状纳米片的稳定化分散及其成膜过程中二维层状限域传质通道修饰和调控这一关键科学问题，采用不同空腔尺寸和功能基的超分子大环化合物原位修饰MoS2二维纳米片并对其进行稳定化改性，探究改性纳米片层间距结构变化及其自组装成膜过程，通过复合膜中超分子的空腔尺寸匹配作用和分子识别能力，在MoS2纳米片层限域空间修饰或构筑传质通道，达到目标组分和溶剂分子的选择性分离和高效渗透；研究不同极性溶剂分子在亲/疏水空腔和二维层状限域通道的传递机理，揭示超分子化合物改性MoS2二维层状膜的分离性能、稳定性、抗污染性及其与膜结构演变的构效关系，为满足实际应用中复杂有机混合体系的高效分离和溶剂回收提供重要的理论依据和研究基础，也为其它二维材料在分离膜领域的研究开辟新思路。

本项目获得小分子醇、大环化合物、聚合物电解质和石墨烯量子点等对原位水热生长的MoS2纳米片层间距调控和稳定化改性新方法，实现了MoS2限域通道的亲疏水性调控和高性能分离；采用分子动力学原理从微观结揭示了两种孔径类型MoS2膜对不同有机溶剂的传输机理，得到不同孔径和化学环境的MoS2纳滤膜的微观分离机理和稳定性变化规律。制备的MoS2/聚电解质杂化膜和MoS2管式陶瓷膜对有机分子的水溶液或有机溶剂溶液均显示优异的纳滤分离性能，同时具有良好的长期运行稳定性，并且对pH值在1-12的酸碱溶液、强极性有机溶剂、高压操作等过程均显示较好的分离稳定性，为高稳定陶瓷膜及其高性能分离提供了较好的应用基础。研究成果发表论文18篇，其中SCI收录13篇，中文核心期刊5篇，参加国际、国内学术会议11人次；获授权中国发明专利8项，其中成果技术转移3项。