A zirconium-based and amine-functionalized metal-organic framework material for adsorption and controlled release of fragrance

Abstract

In this paper, we studied the adsorption and release behavior of various fragrant molecules to zirconium-based and amine-functionalized metal-organic framework materials (MOF) UiO-66-NH2. The results showed that UiO-66-NH2 has almost no difference in the adsorption of non-polar terpenoid fragrances, but there is significant difference in the adsorption of polar ester fragrance. The fragrance-adsorbed UiO-66-NH2 was characterized by SEM, PXRD and FTIR. No structural collapse and crystal form change was found after the adsorption of fragrant molecules. Amine groups in UiO-66-NH2 can form hydrogen bonds with different ester fragrance, which favor the adsorption and sustain release of fragrance. These MOF materials showed much higher adsorption capacity to fragrant molecules than the traditional adsorbent activated carbon. The release kinetics of ester fragrance was studied by headspace-gas chromatography. It was found the release kinetics was consistent with the Korsmeyer-Peppas model and the pore diffusion was the rate-limiting state of its release.