包括电荷转移的法拉第反应通常伴随着主体内部的扩散限制。具有快速离子传输的导电二维框架(2DMOF)可以将电荷转移和多孔结构内部的快速扩散相结合。为了研究由颗粒形态引起的剩余扩散限制,Cu-2,3,6,7,10,11-六羟基三苯撑(Cu3(HHTP)2)的不同合成路线,铜基2DMOF,用于获得片状和杆状MOF颗粒。对于氧化还原活性Li+离子储存,对两种形态进行了系统表征和评估。通过X射线吸收光谱法研究了氧化还原机理,FTIR光谱和原位XRD。通过循环伏安法和阻抗光谱法比较了两种类型关于Li离子存储的动力学性质。可以观察到2DMOF的颗粒形态对电化学Li+离子存储的动力学方面的显著影响。本研究为优化氧化还原活性多孔结构以克服法拉第过程的扩散限制开辟了道路。
Faradaic reactions including charge transfer are often accompanied with diffusion limitation inside the bulk. Conductive two-dimensional frameworks (2D MOFs) with a fast ion transport can combine both-charge transfer and fast diffusion inside their porous structure. To study remaining diffusion limitations caused by particle morphology, different synthesis routes of Cu-2,3,6,7,10,11-hexahydroxytriphenylene (Cu3 (HHTP)2 ), a copper-based 2D MOF, are used to obtain flake- and rod-like MOF particles. Both morphologies are systematically characterized and evaluated for redox-active Li+ ion storage. The redox mechanism is investigated by means of X-ray absorption spectroscopy, FTIR spectroscopy and in situ XRD. Both types are compared regarding kinetic properties for Li+ ion storage via cyclic voltammetry and impedance spectroscopy. A significant influence of particle morphology for 2D MOFs on kinetic aspects of electrochemical Li+ ion storage can be observed. This study opens the path for optimization of redox active porous structures to overcome diffusion limitations of Faradaic processes.