Three-Dimensional Covalent Organic Framework for Efficient Hydrogen Storage through Polarization-Wall Engineering
Jia Chen, Zhuozhuo Tang, Da Zhu, Li Sheng, Zonglong Li, Yang Yang, Jianlong Wang, Yaping Tang, Xiangming He, Hong Xu
Abstract
Covalent organic frameworks (COFs), characterized by high surface areas and tunable pore structures/environments, are regarded as a promising alternative to physisorption H 2 storage materials. However, their interaction with hydrogen is often too weak, necessitating the exploration of strategies to enhance sorption heat. Herein, we strengthened the adsorption induction of COF on H 2 through a polarized wall engineering. The fluorine groups on the pore wall of three-dimensional COFs polarize their surrounding regions, resulting in high sorption heat sites. Due to the enhanced H 2 sorption heat, the total H 2 uptake of 3D-F-COF is up to to 5.96 wt % at 77 K and 90 bar. Moreover, the H 2 adsorption enhancement effect of the polar group does not involve chemisorption, and the material exhibits excellent cycling stability. These results reveal that modulating the H 2 sorption heat by incorporating polar groups is a promising strategy for achieving efficient H 2 storage in porous materials.