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Updated: Sep 8, 2025
Surface Functionalization of Metal-Organic Frameworks for Improved Moisture Resistance
Published on: September 5, 2018
Steric hindrance regulation in hydrogen-bonded organic frameworks: from nonporous to microporous
Xiaokang Wang1, Hongyan Liu1, Meng Sun1
1State Key Laboratory of Heavy Oil Processing, Shandong Key Laboratory of Intelligent Energy Materials, School of Materials Science and Engineering, China University of Petroleum (East China), Qingdao, Shandong 266580, China. dfsun@upc.edu.cn.
Abstract:
Steric hindrance regulation is key for adjusting the pore environment of crystalline porous materials, yet few cases show notable structural changes affecting porosity in hydrogen-bonded organic frameworks (HOFs). Herein, we report two HOFs, UPC-HOF-15 and UPC-HOF-16, constructed with methyl- and methoxy-modified isoreticular tricarboxylic acids, respectively. Due to the distinct steric hindrance, UPC-HOF-15 with hydrogen-bonding between carboxyl groups in two peripheral phenyl rings is nonporous, whereas the hydrogen-bonding in microporous UPC-HOF-16 exists between carboxyl groups in the central phenyl ring and one peripheral phenyl ring, both leaving the remaining carboxyl group forming hydrogen-bonding with solvent molecules. In addition, UPC-HOF-16 exhibits potential for methane purification. This work can provide insights into the discovery of new HOFs via steric hindrance regulation, boosting the diversification of structures and functions.
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