Zinc(Ⅱ)and cadmium(Ⅱ) metal-organic frameworks with naphthalene-1,5-disulfonate and 2,4,5-tri(4-pyridyl)-imidazole: selective fluorescent sensing and photocatalytic properties

【作者】 王军杰； 张道军； 张仁春； 张有娟； 陈静；

【Author】 Jun-Jie Wang;Dao-Jun Zhang;Ren-Chun Zhang;You-Juan Zhang;Jing Chen;School of Chemistry and Chemical Engineering,and Henan Key Laboratory of New Optoelectric Functional Materials,Anyang Normol University;

【机构】 School of Chemistry and Chemical Engineering,and Henan Key Laboratory of New Optoelectric Functional Materials,Anyang Normal University；

【摘要】 The deliberate design of metal-organic frameworks(MOFs) has attracted considerable attention during the past two decades, due to their interesting architectures and tailor-made applications.As typical secondary building units(SBUs), aromatic carboxylate and N-donor ligands have been extensively investigated in past decades due to their strong coordination capability, their large conjugated systems, and the possibility of offering new functional materials. However, to the best of our knowledge, MOFs of a multi-sulfonate containing multidentate N-donor ligands have still been not much [1]. Nowadays, toxic small molecules and harmful pollutants have been demonstrated to adversely affect people’s health. Thus, it is imperative that such pollutants are detected and that organic pollutants in wastewater are rapidly degraded. Among all the detection technologies, luminescence methods have attracted much interest due to their distinguishing advantages, such as short response time, high sensitivity, simplicity and suitability for use either in the solid phase or in solution. Meanwhile, the photocatalytic degradation of organic pollutants has been intensively investigated as an effective technique offering high efficiency, simplicity and good reproducibility. MOFs have already been used to detect small molecules and degrade organic pollutants [2]. Generally, the selectivity and sensitivity of the luminescence detection is mainly dependent on the electron density of the MOFs as well as their ability to donate electrons. Thus, MOFs constructed from electron-rich aromatic fluorescent ligands are excellent candidates for fluorescent sensors. With this in mind, we initiate a strategy of utilising mixed aromatic moieties as fluorescent tags to tune the sensitivity and selectivity of MOFs for detecting small organic molecules and degrading organic pollutants. Considering all the aspects stated above, two novel ZnII and CdII MOFs based on 1,5-naphthalenedisulfonic acid(H2 L) and 2,4,5-tri(4-pyridyl)-imidazole(Htpim), have been synthesized and characterized by elemental analyses, IR spectra and X-ray diffraction analysis. They are almost isostructural and possess 2 D 44 frameworks. They both display highly sensitivity in the detection of nitrobenzene(NB) as fluorescent sensors. Moreover, 1 exhibits a relatively good photocatalytic activity towards the degradation of RhB in aqueous solution under UV irradiation. The degradation ratio of RhB reaches 98.1% after 240 min.更多还原

【Abstract】 The deliberate design of metal-organic frameworks(MOFs) has attracted considerable attention during the past two decades, due to their interesting architectures and tailor-made applications.As typical secondary building units(SBUs), aromatic carboxylate and N-donor ligands have been extensively investigated in past decades due to their strong coordination capability, their large conjugated systems, and the possibility of offering new functional materials. However, to the best of our knowledge, MOFs of a multi-sulfonate containing multidentate N-donor ligands have still been not much [1]. Nowadays, toxic small molecules and harmful pollutants have been demonstrated to adversely affect people’s health. Thus, it is imperative that such pollutants are detected and that organic pollutants in wastewater are rapidly degraded. Among all the detection technologies, luminescence methods have attracted much interest due to their distinguishing advantages, such as short response time, high sensitivity, simplicity and suitability for use either in the solid phase or in solution. Meanwhile, the photocatalytic degradation of organic pollutants has been intensively investigated as an effective technique offering high efficiency, simplicity and good reproducibility. MOFs have already been used to detect small molecules and degrade organic pollutants [2]. Generally, the selectivity and sensitivity of the luminescence detection is mainly dependent on the electron density of the MOFs as well as their ability to donate electrons. Thus, MOFs constructed from electron-rich aromatic fluorescent ligands are excellent candidates for fluorescent sensors. With this in mind, we initiate a strategy of utilising mixed aromatic moieties as fluorescent tags to tune the sensitivity and selectivity of MOFs for detecting small organic molecules and degrading organic pollutants. Considering all the aspects stated above, two novel ZnII and CdII MOFs based on 1,5-naphthalenedisulfonic acid(H2 L) and 2,4,5-tri(4-pyridyl)-imidazole(Htpim), have been synthesized and characterized by elemental analyses, IR spectra and X-ray diffraction analysis. They are almost isostructural and possess 2 D 44 frameworks. They both display highly sensitivity in the detection of nitrobenzene(NB) as fluorescent sensors. Moreover, 1 exhibits a relatively good photocatalytic activity towards the degradation of RhB in aqueous solution under UV irradiation. The degradation ratio of RhB reaches 98.1% after 240 min.更多还原