Recent progress of morphology-controllable covalent organic frameworks: From microscopic to macroscopic scale synthesis and their multifunctional applications

Covalent organic frameworks (COFs) have displayed enormous potentials in catalysis, energy storage, and environmental technologies through their atomic-level ordered lattice structures, yet control over morphologies of COFs from nano-to macroscopic scales remains pivotal for unlocking desired functionalities. Although many reviews have summarized the progress on the synthesis and application of COFs, a comprehensive review covering the more recent synthesis strategies and applications of morphological COFs is being lacking. In this review, we systematically summarized the synthetic strategies, i.e. template-free, hard-templating, and soft-templating approaches, and unravel their formation mechanisms, scalability, and limitations for tailored nanostructure fabrication. We overviewed the morphology-driven enhancement in catalytic activity, biomedicine (i.e. enzyme immobilization, drug delivery), energy devices, and separation systems, while highlighting the scalable shape engineering (i.e. membranes, gels, foams, and fibers). We also given the critical analysis of structure-property interplay, which may provide design principles for next-generation COF materials and perspectives on bridging lab-scale innovations to practical applications.