Design,Synthesis And Properties Of Functional Porous Frameworks Materials

Porous materials play an important role in materials chemistry and industrial production.Metal-organic frameworks?MOFs?and porous organic frameworks?POFs?are two popular classes of porous materials on account of their unique properties and promising application potentials,attracting a lot of research attention.While constructing novel MOFs and POFs is still necessary to expand the family of porous materials,exploring their applications is important to push the research field forward for practical uses.In the past few years,the application scope of MOFs and POFs has been significantly broadened from initial gas capture and separation to other areas such as catalysis,sensing,energy storage and drug delivery.In this work,we focused on the design and synthesis functional MOFs and POFs,and their applications in heterogeneous catalysis and chemical sensing.1.Bifunctional MOF heterogeneous catalysts based on the synergy of dual functional sites for efficient conversion of CO₂.We reported herein a strategy for combining CUS-based MOF?CUS=coordinatively unsaturated metal sites?with ionic liquid?IL?functional sites to form bifunctional heterogeneous catalysts with extra high activity for CO₂ fixation.Based on this strategy,two quaternary ammonium salt and quaternary phosphorus salt ionic liquid functionalized CUS-containing MOF heterogeneous catalysts,MIL-101-N-?n-Bu?3Br and MIL-101-P?n-Bu?3Br,have been prepared for the first time by a post-synthesis modification method.Due to the synergetic role of dual functional sites including Lewis acid sites in the MOF framework and Br ions in the IL functional sites,MIL-101-N?n-Bu?3Br and MIL-101-P?n-Bu?3Br exhibit high catalytic activity for the cycloaddition of CO₂ and epoxide under mild and co-catalyst free conditions,which significantly outperforms other benchmark MOF catalysts.Moreover,such bifunctional catalysts can be easily recovered and recycled several times without leaching and loss of activity.2.A dual functional MOF as a luminescent sensor for quantitatively detecting the concentration of nitrobenzene and temperature.The new luminescent MOF material Zn–TDPAT was synthesized by the solvothermal reaction of H6 TDPAT and Zn?NO3?2·?H2O?6.Zn–TDPAT exhibits stable luminescence and high quantum yield in the solid state at room temperature.This dual functional luminescent MOF sensor represents a significant step forward in detecting the concentration of nitrobenzene and temperature change due to excellent linear correlation between luminescence intensity and nitrobenzene concentration/temperature.3.Multifunctional luminescent POF for selectively detecting iron ions and 1,4-dioxane via luminescent turn-off and turn-on sensing.By selecting the ideal building blocks and conducting the appropriate chemical reaction,we synthesized for the first time a novel multifunctional luminescent POF,named POP-HT,which not only exhibits the function of selectively,qualitatively,and quantitatively recognizing iron ions over other metal ions by significant luminescence quenching but also can detect 1,4-dioxane by prominent luminescence enhancement.In addition,the luminescence quenching and enhancement mechanisms were also studied by both experiment and theoretical calculation.The results indicate that these luminescent characteristics are attributed to the interactions between guest molecules and the POF framework.