Real-time Detection And In Situ Adsorption Imaging Of Iodine

Iodine is closely related to human survival activities.The content of iodine not only has a huge impact on human health,but also is closely related to the sustainable development of the ecological environment.Iodine in the environment is usually transferred with the flow of water in the form of iodide ions,which are oxidized by air to form iodine molecules that exist in atmospheric particles.Therefore,the rapid detection of iodide ions and the adsorption of gaseous iodine have become one of the key problems that need to be solved urgently in today’s society.For the rapid detection of iodine,this thesis developed a new method for visual detection of iodine ions（I^-）at the level of individual microbubbles.For the adsorption of iodine,a dark-field microscopy method was developed to visualize the gaseous iodine adsorption process on a single ZIF-90 particle in situ and in real time,thereby obtaining information on the heterogeneity between particles during the iodine adsorption process.The main research contents include the following two aspects:1.This assay uses the total internal reflection of a single O₂ microbubble at the O₂microbubble glass interface to generate evanescent waves,which are imaged under a dark field microscope.Due to its catalytic ability for H₂O₂ Decomposition,the diameter of a single O₂microbubble in H₂O₂ aqueous solution increases after the introduction of I^-.By this determination,I^-is based on the diameter change of a single O₂ microbubble andμM The level sensitivity and the corresponding dynamic range were determined quantitatively from 0.08 to1 mM.This work represents a key step in the implementation of single oxygen microbubbles as a real-time,visual and quantitative analysis platform that provides a powerful tool for analyzing real water samples,monitoring the migration processes of various nuclides in geographic environments,and early warning of nuclear radiation2.The adsorption of I₂ is found to alter the scattering spectrum of ZIF-90 particles,inducing a distinct color change from bluewhite to yellow.According to correlating the adsorption amount of gaseous I₂ with the change of B value from DFM images,we quantitatively image the adsorption process and estimate the related kinetic parameters at the single particle level.Single particle measurements clarify the large particle-to-particle heterogeneity in adsorption reactivity and significant adsorption activity improvement of ZIF-90 after introduction of linker vacancies,which provides a microscopic understanding of the structure-activity relationship.