Rational design of metal-organic frameworks (MOFs) as hosts for nanoparticles in catalytic applications: concepts, strategies, and emerging trends.

Metal-organic frameworks (MOFs) are a versatile class of porous coordination materials that have found widespread application in various fields, particularly as heterogeneous catalysts. Due to the modular nature and molecular tunability of the metal node-linker coordination in MOFs, they are considered competent hosts for secondary materials in their extensive pore channels. Modifications of the metal nodes or ligand functionalisation in MOFs can improve the anchoring ability of nanoparticles, effectively enhance the nanoparticles' stability, and mitigate the inherent nature of nanoparticles to aggregate. In this review, the synthetic strategies ("ship-in bottle", "bottle-around-ship", and one-pot) and novel characterisation techniques of nanoparticle-MOF (NP-MOF) composites are discussed in detail. The precise determination of nanoparticle-MOF coordination is crucial to shed light on the structure-activity relationships of the catalytic composites. Recognising the synergistic properties of MOFs and metallic nanoparticles, we also explore recent advancements in NP-MOF composites with a special focus on zirconium-based MOFs for catalytic applications within the last five years. Therefore, we aim to aid the reader in evaluating the up-to-date and state-of-the-art advancements concerning the chemistry of nanoparticles and MOFs as catalysts, acting as a path for future learning and optimisations.