Synthesis and characterization of lanthanide metal-organic framework with perylene 3,4,9,10-tetracarboxylate ligand

Abstract

Metal-organic framework (MOF) as a semiconductor material has unique properties and potency to be utilized as a photocatalyst. The superiority of MOF compared to other semiconductor materials is due to the more possibility of adjusting its structure and properties by varying the metal type and organic ligand as the linker to create various framework building blocks, for a number of different applications. In this study, MOFs composed of lanthanide metals (samarium and dysprosium) and PTC ligand (perylene-3,4,9,10-tetracarboxylate), were synthesized and their structural and photochemical properties were characterized. MOFs synthesis were carried out using solvothermal method at 170 ºC, with the variation of metal to ligand mole ratio of 1:1, 2:1 and 1:2 for each metal. FT-IR characterization indicates that in all samples of MOF, PTC ligands coordinate with metals in bidentate ligand mode, which is supported by the existence of peak at around 1770 cm−1 that resembles stretching vibration peak of conjugated C=O anhydride. XRD characterization reveals a quite good crystalline phase in at least two samples, which are Sm-PTC MOF (1:1) and Dy-PTC MOF (1:1), although their crystal types are not known yet. Characterization with UV-Vis DRS shows band gap energy for all samples of MOF ranges from 2.175 eV to 2.328 eV. The obtained band gap energy values indicate that these MOFs will have an excellent respond toward the visible or solar light and, therefore, can be considered as materials suitable for photocatalysis.