Hierarchically porous metal–organic frameworks: synthetic strategies and applications

Abstract

Despite numerous advantages, applications of conventional microporous metal–organic frameworks (MOFs) are hampered by their limited pore sizes, such as in heterogeneous catalysis and guest delivery, which usually involve large molecules. Construction of hierarchically porous MOFs (HP-MOFs) is vital to achieve the controllable augmentation of MOF pore size to mesopores or even macropores, which can enhance the diffusion kinetics of guests and improve the storage capacity. This review article focuses on recent advances in the methodology of HP-MOF synthesis, covering preparation of HP-MOFs with intrinsic hierarchical pores, and modulated, templated and template-free synthetic strategies for HP-MOFs. The key factors which affect the formation of HP-MOF architectures are summarized and discussed, followed by a brief review of their applications in heterogeneous catalysis and guest encapsulation. Overall, this review presents a roadmap that will guide the future design and development of HP-MOF materials with molecular precision and mesoscopic complexity.

Promotion effect of metal phosphides towards electrocatalytic and photocatalytic water splitting

“…In addition, MOFs, a kind of functional material exhibiting large specific surface areas and pore size distributions, multiple active sites, and clipping structures, were usually used as precursors to prepare metal phosphides 36‐38 . MOF‐derived nickel phosphide (Ni 2 P) was prepared via a simple, cost‐effective procedure using inexpensive and abundant elements 39 .…”

Strategies for Pore Engineering in Zirconium Metal-Organic Frameworks

“…A summary of methods to introduce larger pores in MOFs, including bottom-up and top-down approaches, will not be discussed in detail since this topic has been elaborately ll Chem 6, 2902-2923, November 5, 2020 2907 Review reviewed elsewhere. 15,74,75 Instead, here we provide discussions and insights into the combination of MOF pores via precise molecular engineering.…”

“…The pore-combined hierarchical structures are considered as promising candidates for enzyme immobilization, guest capture, and other applications. 15,[83][84][85]…”

“…In recent years, investigations into controlling the complexity of MOF pore environments have steadily increased. 7,15 The high tunability of organic components in MOFs has allowed for the rapid development of synthetic methods for pore environment modification. Various pores with precisely controlled shapes and sizes can be rationally constructed using cluster-ligand assembly processes through the selection of ligands with specific connectivities, sizes, and conformations.…”

Metal–Organic Framework-Based Solid Acid Materials for Biomass Upgrade

“…Moreover, the inorganic-organic hybrid nature endows MOFs with facile modification strategies [12,13]. In terms of using MOF materials in heterogeneous catalysis, the larger surface area allows accommodating more active species per unit weight [14]; the appropriate pore dimension enables good molecule sieving function toward both substrates and catalytic products [15][16][17]; the versatile modification can further incorporate desired active moieties into MOF materials for performance improvement [18,19]. Therefore, MOFs or MOF-based composites are considered feasible candidates for heterogeneous catalysis, particularly acting as novel solid acid catalysts for biomass upgrade [20][21][22][23].…”