A fluorene based covalent triazine framework with high CO2 and H2 capture and storage capacities
A fluorene based covalent triazine framework with high CO2 and H2 capture and storage capacities
复制标题
DOI：
10.1039/c3ta15417c
复制
发表时间：
2014-01-01
影响因子：
11.9
通讯作者：
Lotsch, Bettina V.
中科院分区：
文献类型：
--
作者：
Hug, Stephan;Mesch, Maria B.;Lotsch, Bettina V.
近年来，多孔有机聚合物已成为捕获和储存燃烧后二氧化碳的焦点。共价三嗪框架（CTFs）是一种富氮多孔聚合物，具有较高的化学稳定性和热稳定性，具有增强的可调性和功能性。在这项工作中，提出了一种新的基于芴构建块的共价三嗪框架，并全面阐明了其局部结构，孔隙率以及CO2捕获和H-2储存的能力。在300-600℃的离子热条件下，以ZnCl2为Lewis酸性三聚化催化剂和反应介质合成了该骨架。在较低温度下合成的材料大多具有超微孔和中等表面积，通过CO2吸附探测(300℃时为297 m(2) g(-1))，而在较高的合成温度下，孔隙率显著增加，导致表面积超过2800 m(2) g（-1）。在350℃下获得的CTF具有高比例的微孔和1235 m(2) g（-1）的表面积，在273 K （4.28 mmol g(-1)）下表现出优异的CO2吸附能力，是所有多孔有机聚合物中观察到的最高吸附能力之一。此外，该材料的CO2/N-2选择性高达37。在77 K和20 bar条件下的氢吸附量为4.36 wt%，与其他持久性有机污染物相当，但在迄今所研究的所有CTFs中是最高的。
Porous organic polymers have come into focus recently for the capture and storage of postcombusted CO2. Covalent triazine frameworks (CTFs) constitute a nitrogen-rich subclass of porous polymers, which offers enhanced tunability and functionality combined with high chemical and thermal stability. In this work a new covalent triazine framework based on fluorene building blocks is presented, along with a comprehensive elucidation of its local structure, porosity, and capacity for CO2 capture and H-2 storage. The framework is synthesized under ionothermal conditions at 300-600 degrees C using ZnCl2 as a Lewis acidic trimerization catalyst and reaction medium. Whereas the materials synthesized at lower temperatures mostly feature ultramicropores and moderate surface areas as probed by CO2 sorption (297 m(2) g(-1) at 300 degrees C), the porosity is significantly increased at higher synthesis temperatures, giving rise to surface areas in excess of 2800 m(2) g(-1). With a high fraction of micropores and a surface area of 1235 m(2) g(-1), the CTF obtained at 350 degrees C shows an excellent CO2 sorption capacity at 273 K (4.28 mmol g(-1)), which is one of the highest observed among all porous organic polymers. Additionally, the materials have CO2/N-2 selectivities of up to 37. The hydrogen adsorption capacity of 4.36 wt% at 77 K and 20 bar is comparable to that of other POPs, yet the highest among all CTFs studied to date.