Reticular chemistry within three-dimensional covalent organic frameworks for multiple applications

Abstract

This review summarizes the advances in rational design and synthesis of 3D COFs guided by reticular chemistry and briefly discusses recent progress in gas storage and separation, catalysis, fluorescence, batteries, conductivity, and drug delivery.

Mitigating the Shuttle Effect: 3D Covalent Organic Frameworks Anchoring Polysulfides for High-Performance Lithium–Sulfur Batteries

“…In contrast to layer structures assisted by π–π stacking of 2D COFs, the whole 3D skeletons are solely connected by covalent bonds to form an extended network in 3D COFs, which endows it with high surface area, large pore volume, and complicated pore structures such as interpenetrated channels and cages. , These favorable features can enhance the encapsulation of sulfur and inhibit the shuttle effect of LSBs . 3D COFs offer greater benefits in mass transfer and diffusion for LSBs.…”

“…26,27 These favorable features can enhance the encapsulation of sulfur and inhibit the shuttle effect of LSBs. 28 3D COFs offer greater benefits in mass transfer and diffusion for LSBs. However, to the best of our knowledge, the exploration of 3D COFs for LSB is still in its infancy.…”

Photochromic radical states in 3D covalent organic frameworks with zyg topology for enhanced photocatalysis

“…This means that building units with proper lengths are required for constructing such photochromic COFs. In view of the reticular chemistry [ 24 , 25 ], compared with the layer-by-layer stacking of 2D COF structures, the 3D interconnection of the building units in 3D COFs can afford more pathways for electron transfer and stabilize separated photoinduced charges through stronger electrostatic attraction interactions. In addition, 3D COFs with meso-porosity (with pore diameter larger than 2 nm) [ 26 ] can usually accommodate more accessible donor and acceptor sites with good catalytic activity [ 27 ].…”

“…In the 3D COFs database, the 4-connected building blocks with tetrahedral ( T d ) symmetry were mostly used to connect with other building units in [4 + 2], [4 + 3] and [4 + 4] modes to form topologies such as dia, bor and pts in the early studies [ 30–32 ]. In recent years, 3D COFs based on higher connectivity building units have been synthesized with new topologies featuring [6 + 2], [6 + 3], [6 + 4], [6 + 6], [8 + 2] or [8 + 4] nets [ 25 ]. Among these, 3D COF structures based on [6 + 4] net were constructed showing high surface area, high structural stability, an absence of structural interpenetration and decent catalytic properties.…”