发布日期:2020/7/10 9:49:04
Covalent Organic Frameworks (COFs) are organic, crystalline, highly porous materials
attractive for applications such as gas storage, gas separations, catalysis, contaminant adsorption and
membrane filtration. Activation of COFs removes adsorbed solvents and impurities, but common methods
for COF activation can result in collapse of porous structure and loss of accessible surface areas. Here,
we present a study of the impact of solvent surface tension on the activation process and demonstrate that
activation using the ultralow surface tension solvent perfluorohexane (PFH) is simple and effective for a
range of COF materials. We synthesized six different imine-based COFs through imine condensation
reactions between tris(4-aminophenyl) benzene (TAPB) or 2,4,6-tris(4-aminophenyl)-1,3,5-triazine
(TAPT) and multi-functional di- and tri-benzaldehydes with different aromatic substituents. For each
COF, we performed a solvent wash followed by vacuum drying using six solvents varying in surface
tension from 11.9 – 72.8 mN m-1. Through powder X-ray diffraction (PXRD) measurements combined
with nitrogen adsorption and desorption analysis, we found that some COF chemistries readily lost their
porosity during activation with higher surface tension solvents while others were more robust. However,
all COFs could be effectively activated using PFH to produce materials with excellent crystallinity and
high surface areas, comparable to those for samples activated using supercritical CO2. This work
demonstrates that the solvent surface tension used during activation has a strong impact on potential pore
collapse, and activation using PFH provides a simple and effective activation method to produce COFs
with excellent crystallinities and pore structures.

下一篇:A Glycosylated Covalent Organic Framework Equipped with BODIPY and CaCO3 for Synergistic Tumor Therapy
上一篇:Fully Conjugated Donor-Acceptor Covalent Organic Frameworks for Photocatalytic Oxidative Amine Coupling and Thioamide Cyclization

联系我们

  • 地址:长春市北湖科技开发区
    盛北大街 3333号 ​长春北湖科技园产业三期H13栋
     
  • 电话: 0431-80534353 
    传真: 0431-80534353 
    邮箱: et@chemextension.com

©Copyright 2017-2018 吉林中科研伸科技有限公司  吉ICP备17007642号-1
技术支持:KuuJia