Iron doping enhances the bind stability of transpiration water to Zr-based MOFs packaging

The metabolic processes of fruits induce water vapor condensation in packaging, creating a high-humidity microenvironment that exacerbates the proliferation of microorganisms and causes food spoilage. Therefore, a Fe/Zr bimetallic organic framework (Fe-MOF-801) packaging (i.e., FeMGCF) with high binding stability to transpiration water was prepared based on transition metal Fe doping strategy, and the mechanism of its enhanced binding stability towards transpiration water was investigated. The results indicate that Fe enhances the interaction between MOFs and H₂O by promoting the charge depletion at the O sites coordinated with Zr, thereby increasing the aggregation tendency of H₂O in the T₁ and T₂ cavities (characterized by strong hydrogen bonding) of Fe-MOF-801, which increased the binding energy of MOFs to H₂O by 29.6 %. Accordingly, the application of FeMGCF packaging extended the shelf life of tomatoes by 6 days and delayed the degradation of lycopene and anthocyanins during postharvest tomato preservation.