Preparation And Application Of Metal-Organic-Framework-Based Fluorescent Materials

Metal-organic framework materials（MOFs）are a type of high-crystalline porous material composed of metal ions and organic ligands,which have been widely studied in the past two decades due to their high porosity,excellent structural stability,and ease of synthesis.Among them,luminescent metal-organic framework materials（LMOFs）have flexible structures,rich luminescent sites,and unique luminescent properties,making them promising materials for applications in displays,lighting,fluorescence detection,and sensing.In this thesis,Eu/Y-MOF,FITC/RhB/CD@ZIF-8,and Eu W₁₀/Zr-MOF composite materials were prepared.The morphology,structure,and composition of the materials were analyzed by characterizations including scanning electron microscopy,energy-dispersive X-ray spectroscopy,X-ray diffraction,Fourier transform infrared spectroscopy,and X-ray photoelectron spectroscopy.The fluorescence properties of the materials were tested using fluorescence spectroscopy.First,a series of LMOFs materials were prepared employing rare earth ions,and the luminescent color of the LMOFs materials was effectively tuned by adjusting the ratio of Eu³⁺,Y³⁺and Tb³⁺.White fluorescent Eu/Y-MOF materials were successfully obtained and used for the detection of Fe³⁺and Co²⁺.Secondly,organic fluorescent dyes and carbon quantum dots（CDs）are fluorescent materials with excellent luminescent properties.By combining fluorescein isothiocyanate（FITC）,rhodamine B（RhB）,and CDs with ZIF-8,composite materials with different emission colors,including white fluorescence,can be obtained by changing the ratio of FITC,RhB and CDs in the ZIF-8 pores.The prepared FITC/RhB/CD@ZIF-8 composite materials can be used for the detection of Fe³⁺.Finally,applying the polyoxometalate Eu W₁₀ as the red-emitting material and Zr-MOF as the blue-emitting material,cyan,beige,and pink Eu W₁₀/Zr-MOF composite materials were obtained.The optimized composite was employed for the detection of Fe³⁺and Cr₂O₇^2-.The prepared materials possess high sensitivity and short response time,and have broad application prospects in fluorescence sensors.