A MICROPOROUS HYDROGEN-BONDED ORGANIC FRAMEWORK FOR HIGHLY SELECTIVE C2H2/C2H4 SEPARATION AT AMBIENT TEMPERATURE

摘要

Porous hydrogen-bonded organic frameworks (HOFs) have lagged significantly behind metal-organic frameworks (MOFs) in terms of their development on their framework design, topological rationalization, and functional exploration, although the concepts to construct such porous materials by making use of hydrogen bonding and coordination bonding, respectively, were proposed during the same period of time. Such a situation is mainly because of the weaker hydrogen bonding interactions within HOFs, which are typically not strong enough to stabilize the frameworks and thus to establish their permanent porosities. In fact, although a large number of hydrogen-bonded organic frameworks have been structurally characterized and reported in the literature, only recently a few HOFs have been realized to show permanent porosities. It is expected that the establishment of these few porous HOFs will initiate the rebound interest in the exploration of functional porous HOF materials for their potential applications in gas storage and separation, sensing, and heterogeneous catalysis, thus extensive research endeavors will be pursued to figure out the basic and strong hydrogen bonding motifs to stabilize the frameworks, and to rationalize the basic principle to construct the frameworks of the desired topologies, and to control the pore sizes, dimensions, and functionalities of the porous HOF materials for their diverse applications. On the one hand, some new hydrogen bonding motifs will need to be explored for the construction of porous HOFs; on the other hand, the few hydrogen bonding motifs which have been realized to stabilize the frameworks will be examined comprehensively on their universal applicability and feasibility to build a series of expanded HOFs whose pore sizes and functionalities can be systematically tuned and explored for their applications.