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Updated: Aug 16, 2025
Synthesis of Single-Crystalline Core-Shell Metal-Organic Frameworks
Published on: February 10, 2023
Tuning Magnetic and Photophysical Properties of Luminomagnetic Metal-Organic Framework Composites in an Inverse
Marcel T Seuffert1, Tim Granath2, Thomas Kasper1
1Institute of Inorganic and Analytical Chemistry, Justus Liebig University Giessen, Heinrich-Buff-Ring 17, 35392, Giessen, Germany.
Abstract:
Luminomagnetic composites have been synthesized that allow for an individual tuning of luminescence intensity, chromaticity and magnetization by combination of superparamagnetic, citrate-stabilized iron oxide nanoparticles with the luminescent MOFs 3 ∞ [Ln2 (BDC)3 (H2 O)4 ] (Ln=Eu, Tb; BDC2- =terephthalate). The components are arranged to a concept of inverse structuring compared to previous luminomagnetic composites with MOF@magnetic particle (shell@core) composition so that the luminescent MOF now acts as core and is covered by magnetic nanoparticles forming the satellite shell. Thereby, the magnetic and photophysical properties are individually tuneable between high emission intensity (1.2 ⋅ 106 cps mg-1 ) plus low saturation magnetization (6 emu g-1 ) and the direct opposite (0.09 ⋅ 106 cps mg-1 ; 42 emu g-1 ) by adjusting the particle coverage of the MOF. This is not achievable with a core-shell structure having a magnetic core and a dense MOF shell. The composition of the composites and the influence of different synthesis conditions on their properties were investigated by SEM/EDX, PXRD, magnetization measurements and photoluminescence spectroscopy.
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