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Updated: Sep 23, 2025
Synthesis and Characterization of Functionalized Metal-organic Frameworks
Published on: September 5, 2014
Synthesis, structure, and fluorescence properties of a calcium-based metal-organic framework
Daichi Kojima1, Tomoe Sanada1, Noriyuki Wada2
1Department of Applied Chemistry, College of Life Sciences, Ritsumeikan University 1-1-1 Noji-Higashi Kusatsu-City Shiga 525-8577 Japan kojimaka@sk.ritsumei.ac.jp.
Abstract:
The solvothermal reaction of a mixture of calcium acetylacetonate and 1,4-naphthalenedicarboxylic acid (H2NDC) in a solution containing ethanol and distilled water gave rise to a metal-organic framework (MOF), {(H3O+)2[Ca(NDC)(C2H5O)(OH)]}4·1.1H2O. This MOF possesses a new structure composed of calcium clusters and H2NDC linker anions and shows a unique fluorescence property; it exhibits a fluorescence peak at 395 nm (λ ex = 350 nm) at room temperature, which is blue-shifted compared with that exhibited by the free H2NDC ligand. One of the possible mechanisms for this fluorescence is likely attributable to a ligand-to-metal charge transfer (LMCT) transition and is the first example of a calcium-based MOF exhibiting blue-shifted fluorescence due to LMCT.
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