SYNTHESIS AND PHOTOPHYSICAL PROPERTIES OF MIXED LOFs
LOFs; lanthanides; antenna effect; photoluminescence; morphology
In this work was synthesized a new metal-organic frameworks containing lanthanide ions (LOFs) by solvothermal method at 1200C, using as the organic component terephthalic acid (1,4-H2BDC). Three matrices containing gadolinium doped with 5 mol% Eu3+ ions were prepared (Eu/Gd-1,4-BDC-MOFs). The study focused on varying the synthesis time (3, 5 and 7 days) to understand the influence of this parameter on the morphological and luminescent properties of the net. The samples in powder form, were characterized by X-ray Diffraction (XRD), Attenuated total reflectance Fourier transform infrared spectroscopy (FTIR-ATR), Scanning Electronic Microscopy (SEM), Thermogravimetric Analysis (TGA) and Photoluminescence (PL). The results suggest that increased synthesis time has a significant influence on the morphology of the crystals. It was observed from the excitation and emission spectra intramolecular energy transfer between the ligand and the levels of Eu3+, which is not expected to MOFs type Eu-1,4-BDC. It was inferred from that that the high paramagnetic ion Gd3+ present in the matrix, it was essential to increase the antenna effect, giving a strong red emission from the sample.