The Preparation Of The Ratio Fluorescent Sensor Based On Quantum Dots@Porous Materials For Formaldehyde Detection

Formaldehyde（FA）is a common environmental pollutant with high reactivity,toxicity,and water solubility(4000 g·L^-1 at 20 ^oC).As the simplest aldehyde,formaldehyde has a wide range of applications in the chemical industry,such as the production of detergents and plastics,wood processing,and pharmaceutical synthesis.The existence of formaldehyde in air or water poses various threats to the environment and human health.In recent years,various formaldehyde detection methods have emerged.Traditional formaldehyde detection methods,including spectrophotometry,colorimetry,high-performance liquid chromatography,gas chromatography,ion chromatography,and polarography,require expensive detection equipment and trained personnel,and have longer detection times.To overcome these limitations,this study proposes the use of a ratio fluorescent sensor for formaldehyde detection.Ratio fluorescent sensors can construct a self-calibration system based on the intensity ratio of fluorescent emission peaks in the system,and can eliminate interference from the background and experimental environment through self-calibration,improving the accuracy and reliability of detection.In aqueous solutions,ratio fluorescent sensors can be applied to the detection of harmful substances such as formaldehyde,providing strong protection for environmental protection and human health.This paper focuses on the detection of formaldehyde in aqueous solutions using porous material ratio fluorescent sensors,and conducts a series of related studies,including:（1）Two responsive ratio fluorescent sensors,CDs@UiO-66-NH₂ and CDs@MA-IPA,were prepared using CDs as guest molecules and UiO-66-NH₂ and MA-IPA as substrate materials by hydrothermal synthesis,and the factors affecting the fluorescence properties of the two ratio fluorescent sensors were discussed in detail.Experimental results show that the two ratio fluorescent sensors exhibit excellent linear relationships and low detection limits（0.41μM and 0.29μM）in the range of formaldehyde concentrations from 0 to 300μM.Interference experiments and the preparation of formaldehyde detection test paper demonstrate that the ratio fluorescent sensors prepared in this chapter are expected to be applied to the analysis and detection of formaldehyde in actual samples.（2）A reference fluorescent plus responsive fluorescent ratio fluorescent sensor,CdTe@γ-CD-MOF,was prepared using CdTe as guest molecules andγ-CD-MOF as substrate materials,and the factors affecting the sensing of formaldehyde by this ratio fluorescent sensor were studied.The experimental results demonstrate that CdTe@γ-CD-MOF ratio fluorescent sensor exhibits an excellent linear relationship and low detection limit（0.65μM）for formaldehyde detection.Based on CdTe@γ-CD-MOF ratio fluorescent sensor,formaldehyde detection test paper was prepared,further expanding the application range of CdTe@γ-CD-MOF ratio fluorescent sensor.This paper synthesized three types of porous material ratio fluorescent sensors for formaldehyde detection in aqueous solutions.All three ratio fluorescent sensors make up for the shortcomings of traditional detection methods in formaldehyde detection and providing an important theoretical basis for formaldehyde detection.