Peparation Of EuCe Codoped-BTC Complex And Its Fluorescence Properties

In recent years, fluorescent sensing material has become more and more important in the field of material science and has been get a lot of corcern. Fluorescent sensing material, which has the advantage of high sensitivity, easy to detect and real-time detection, has been flourishing in the field of molecular recognition and application of chemical sensors. This research takes a kind of rare earth element europium as the metal center, and take the trimesic acid as the organic ligand, in order to synthesize complex. Our work focus on the posiblity of detecting fluorescent chemical sensing. Based on this research, we take two kinds of rare earth elements to synthesize complex. Meanwhile we also focus on the posiblity of this complex that can use as fluorescent chemical sensing material. In this paper, the synthesis of fluorescent sensing material can be use for detecting small molecule organic compounds, which even can detect the concentration of toxic small molecule compounds in the future.At first, we optimized the synthesis conditions of the Eu-BTC complex with the method of hydrothermal synthesis and took the best synthesis conditions in order to test fluorescence properties of the Eu-BTC complex. The results show the best synthesis conditions: reaction temperature is 80 ℃; the mixed solvent is DMF, Et OH and H2 O, and the volume ratio is 3: 3: 2; molar ratio of Eu（NO₃）₃·6H₂O / BTC is 1: 1; the reactant concentration（use Eu（NO₃）₃·6H₂O as standard） is 0.01 mol/L; the reaction time is 24h; the replacement solvent is methanol; vacuum drying temperature is 140 ℃. Using this method, the complex has very strong fluorescence intensity when it is in the 20% DMF solvent, but it can not achieve the fluorescence sensing in DMF or Et OH or Me OH solvent.Secondly, we explored the synthesis of Eu/Ce-BTC complex, which has studied affection of the molar ratio of Eu（NO₃）₃·6H₂O and Ce（NO₃）₃·6H₂O to the complex. In this paper, the molar ratio of Eu（NO₃）₃·6H₂O and Ce（NO₃）₃·6H₂O is 9:1, 8:2, 7:3, 6:4, 5:5. In order to knowing the structure of the complex,X-ray diffraction（XRD）, Surfacce electron microscopy（SEM）, Thermal gravimetric analysis（TGA）, Infrared analysis（IR）, X- ray photoelectron diffraction（XPS） was used to characterize the complex morphology and sructures. The results show: the complex can used as fluorescent sensing material for detecting small molecule organic compounds. When the molar ratio of Eu（NO₃）₃·6H₂O and Ce（NO₃）₃·6H₂O is 6:4, 7:3, 9:1, the complex has the higher accuracy for dectecting the concentration of DMF, Et OH, Me OH respectively.