Advancing from MOFs and COFs to Functional Macroscopic Porous Constructs

Metal-organic frameworks (MOFs) and covalent-organic frameworks (COFs) are the highly porous rising stars of reticular chemistry. However, most face challenges such as poor macroscopic structuring capability, inadequate mechanical robustness, and inaccessible porosities for target reactants, which hinder their practical applications. This review explores various strategies to assemble MOFs and COFs into macroscopic 3D-structured multi-scale porous structures, such as aerogels, foams, and sponges. The methods discussed include direct mixing, self-shaping, in situ growth, template-assisted approaches, and 3D printing. These strategies enable macroscopic MOF or COF porous structures to achieve excellent mechanical strength and tunable porosity from the molecular level and micro-scale up to the macroscopic level. This structural tunability allows the MOF or COF porous structures to outperform their neat powders by making their micro- and meso-porosities more accessible to target reactants. Such improvements pave the way for the functionality of MOF or COF species at larger scales, addressing urgent societal needs, including environmental remediation, CO₂ capturing, value-added catalytic reactions, water harvesting, electromagnetic (EM) shielding, and beyond.