Construction Of Fluorescent MOFs For The Detection Of Pollutants In Water

Metal-organic frameworks(MOFs),due to its diverse structure and uniform pore rate have attracted wide attention.It has become the fastest growing areas in chemistry and materials science over the past two decades.As a class of porous crystalline material,having a periodic network structures of MOFs via node(metal ions/clusters,also known as two building units)formed of a metal containing inorganic and organic self-assembled joint.The organic joints are very diverse,mainly based on carboxylates,N-donor groups and even phosphonates,and are available in a variety of formulations.The structure is not only rich and interesting but also designs and customizable,so it can be designed for Fluorescent probes,electrochemical aspects.In this paper,1,2-phthalic acid and bbi were used as building blocks of organic molecules,and supported by bridged bisimidazole ligands,and Cd2+ ions and Zn2+were used to obtain novel,stable fluorescent properties of MOFs by solvothermal method.Single crystal data were obtained by X-ray diffraction,and the single crystal structure was solved by SHELXTL,X-seed and diamond software.Finally,the fluorescence properties of MOFs were tested by fluorescence spectrophotometer.1.Cd-MOF as a fluorescent probe for the detection of Fe3+A novel,fluorescent MOFs material was obtained by solvothermal method using phthalic acid and bbi as organic molecular building blocks and bridging bisimidazole ligands with Cd2+ ions.The single crystal data was tested by using a single crystal diffractometer,and the single crystal structure was solved using SHELXTL,XSeed,and Diamond software.The single crystal number is CCDC1576307,and the single crystal data is stored in the Cambridge database.The MOFs material has stable fluorescence performance in water by fluorescence spectrophotometer,so it has a promising application in fluorescence sensors.The use of Cd-MOF as a fluorescent probe can effectively detect Fe3+ in water,and has high selectivity,high sensitivity and good stability.2.Detection of CRO by Cd-MOF as a fluorescent probeBecause of the abuse of antibiotics,domestic water is contaminated by antibiotics,so the detection of antibiotics is very necessary.Titration experiments were performed on each of the 17 antibiotic solutions selected.At the same concentration,CRO compared the other antibiotics,CRO makes the fluorescence intensity of the fluorescent probe quenched more,and the more obvious as the concentration increases,which indicates that Cd-MOF is used as a fluorescent probe to detect CRO.There is obvious selectivity.And through the Stern-Volmer(SV)equation:I0/I=Ksv[Q]+1,the Ksv value is calculated.The calculated Ksv value is 3.51×105M-1,and then the detection limit is 55 ppb calculated by Ksv.In the time effect experiment,during the process of CRO concentration from low to high,Cd-MOF as a fluorescence is very sensitive to the detection of CRO,and the fluorescence intensity is quenched in 20 seconds,and then reaches a steady state.Cd-MOF is highly sensitive to CRO detection as a fluorescent probe.To investigate the stability of Cd-MOF as a fluorescent probe,we designed a stability test.In the pH stability experiment,we found that Cd-MOF is used as a fluorescent probe.When the pH of the solution is 4-11,the detection of CRO is not affected by pH.In the selective optimization experiment,the experimental results show that other antibiotics are present and the concentration is higher than CRO,Cd-MOF can still effectively detect CRO as a fluorescent probe,which is not interfered by other antibiotics,which indicates that the probe has strong anti-interference.3.Zn-MOF as a fluorescent probe for the detection of ascorbic acidWe designed and synthesized a two-dimensional Zn-MOF material based on the coordination of phthalic acid and bbi as ligands with Zn(?).The single crystal number is CCDC1837644 and the single crystal data is stored in the Cambridge data center.Zn-MOF can be used as a fluorescent probe to effectively detect ascorbic acid.Good fluorescence properties make Zn-MOF a potential fluorescent material for the detection of ascorbic acid.Among many amino acid solutions,only the ascorbic acid solution can quench the fluorescence of Zn-MOF,and the detection limit of ascorbic acid is 1.704 ppb,which indicates that Zn-MOF has high selectivity and high sensitivity to trace ascorbic acid.And the ultraviolet absorption of ascorbic acid between 240 nm and 400 nm hinders the absorption of Zn-MOF,resulting in fluorescence quenching.In the interference experiment,the detection of ascorbic acid by Zn-MOF can be stably detected even in the presence of other amino acids,which indicates that the detection of ascorbic acid has good anti-interference performance.