正构烷烃在金属有机骨架上限域作用的介尺度机制及定向调控

ZIFs具有吸附分离正构烷烃的独特优势和诱人应用前景，吸附过程的介尺度机制及调控是决定过程效率的亟待解决的关键科学技术问题。本项目针对材料层次的介尺度问题，基于纳微结构设计及调变构造具有特征介尺度结构的ZIFs材料，借助多种分析技术对ZIFs进行多尺度表征；聚焦正构烷烃在ZIFs介尺度空间内的限域作用，结合SAXS、Operando Raman等多种手段揭示介尺度结构的形成、介稳特性和演化规律；分别采用DFT和MMC方法模拟研究限域作用的微观特性和介尺度行为；建立正构烷烃在ZIFs介尺度空间内限域作用的热力学参数与介观结构以及微观组成的关系，从热力学角度阐明材料层次上的介尺度作用机制并构建理论模型；通过调变材料介尺度结构实现对吸附过程介尺度行为的定向调控。丰富和完善共性介尺度问题的普遍机制及通用理论体系，推动多学科的交叉与协同创新。

Owing to their promising advantages, ZIFs are finding the potential applications in adsorption separation of normal paraffins. However, the mechanism and directed regulation of mesoscopic effects involved in the adsorption process are becoming the urgent problems in both scientific research and technological applications. Our current project is aimed at solving the mesoscopic problems from the material level. Based on the structural design and manipulation in nano- and micro-scale, ZIFs materials bearing mesoscopic structures are to be formed. In addition, the multiscopic structures of ZIFs can be characterized by using multi-technical analyses. To focus on the confinement of normal paraffins in mesoscopic voids, the formation, meta-stability and evolution of mesoscopic structures can be revealed through coupling with multiple analysis techniques including SAXS and Operando Raman. Moreover, DFT and MMC modeling will be carried out to describe the microscopic and mesoscopic behaviors of the confinement event. The relationships among thermodynamic parameters, mesoscopic structures and microscopic compositions will be observed. From the material level, the mesoscopic mechanism should be explained and the theory model should be established. Furthermore, the mesoscopic behaviors in adsorption process are expected to be regulated by changing the mesoscopic structures of materials. The research will help enrich and accomplish the general mechanism as well as the theory system behind the common mesoscopic problems, and push the multi-disciplinary collaborative innovation forward.