Encapsulation of InP/ZnS quantum dots into MOF-5 matrices for solid-state luminescence: ship in the bottle and bottle around the ship methodologies.

The utilization of InP-based quantum dots (QDs) as alternative luminescent nanoparticles to cadmium-based QDs, known for their toxicity, is actively pursued. However, leveraging their luminescent attributes for solid-state applications presents challenges due to the sensitivity of InP QDs to oxidation and aggregation-caused quenching. Hence an appealing strategy is to protect and disperse InP QDs within hybrid materials. Metal-organic frameworks (MOFs) offer a promising solution as readily available crystalline porous materials. Among these, MOF-5, composed of {Zn4O}6+ nodes and terephthalate struts, can be synthesized under mild conditions (at room temperature and basic pH), making it compatible with InP QDs. In the present work, luminescent InP QDs are successfully incorporated within MOF-5 through two distinct methods. Firstly, employing the bottle around the ship (BAS) approach, wherein the MOF was synthesized around2 the QDs. Secondly, utilizing the ship in the bottle (SIB) strategy, the QDs were embedded via capillarity into a specially engineered, more porous variant of MOF-5. Comparative analysis of the BAS and SIB approaches, evaluating factors such as operational simplicity, photoluminescence properties, and the resistance of the final materials to leaching are carried out. This comparative study provides insights into the efficacy of these strategies for the integration of InP QDs within MOF-5 for potential solid-state applications in materials chemistry.