The Construction Of Electrochemical Sensors Based On A Series Of Metalloporphyrin Coordination Polymers

Metal organic frameworks (MOFs) have many advantages, such as large specific surface area, high spatial structure diversity and multi functionality. The MOFs used porphyrin as organic ligand , not only have the advantages of adjustable pore and large surface area etc., but also have the advantages of photoelectric performance which come from porphyrin ligands. The metal porphyrin frameworks become a hot spot for research applied in object selective adsorption, hydrogen storage,heterogeneous catalysis and so on. However, the application in the area of electrochemistry is rare, especially the electrochemical sensing. This paper references the four carboxyl phenyl porphyrin ligand (H2TCPP) were synthesized firstly according the references, then a series of double metal CuCdTCPP, CoCdTCPP and CuCoCdTCPP three metal coordination polymers were synthesized with H2TCPP as ligand, and their application in electrochemical sensor was studied. The main contents are as follows:1?Synthesis and characterize a series of coordination polymers with H2TCPP as ligands. Using H2TCPP as ligand, metal cadmium, cobalt, with two valence copper,cadmium ions with d Empty trackas as metal center to form metal porphyrin framework easily. In this paper, the synthesis of metal porphyrin coordination polymers with different ratios were prepared by solvothermal method. By using X-ray diffraction (XRD), transmission electron microscopy (TEM), infrared spectroscopy (IR), ultraviolet visible absorption spectroscopy (UV-vis) and thermogravimetric analysis (TG), inductively coupled plasma atomic emission spectrometer (ICP) were used to characterize the products. XRD shows that the polymer and references in the synthesis of polymers with the same structure but not isomorphous. TEM showed that the various coordination polymers were irregular small particles with a width of 2 ?m and a length of about 4 ?m. Infrared and ultraviolet spectra show that H2TCPP is coordinated with the metal, and the coordination mode is also shown by IR. Thermogravimetric analysis shows that when the feed ratio is the same as that in the literature, the synthetic polymer has the same crystalline water and crystalline DEF as in the literature, ICP determines the proportion of metal in the coordination polymers.2?The application of electrochemical properties based on a series of coordination polymers used H2TCPP as ligands. In this paper, the synthesis of a series of coordination polymers with a plurality of metal active center can be constructed different electrochemical sensor because of the difference of active metal center, a series of coordination polymers were modified on glassy carbon electrode to make polymer /GCE electrode, in order to improve the performance of the electrochemical sensor, a layer of multi walled carbon nanotubes film was first modified on the surface of the electrode, and then the coordination polymer was modified, Cyclic voltammetry and chronoamperometry were used to study the performance of/MWCNTs/GCE electrode for sodium nitrite and hydrogen peroxide, the range of chronoamperometry working potential range of detection of sodium nitrite and hydrogen peroxide was determined according the response of CV , then the detection sensitivity comparison of different working potential, establish the best working potential, finally to detect hydrogen peroxide and sodium nitrite in the best potential.This series of coordination polymers in the modified multi walled carbon nanotubes, and can enhance the sensitivity of detection of hydrogen peroxide and sodium nitrite, so this series of coordination polymers can be used to construct the dual function of electrochemical sensor. The sensitivity of seven kinds of coordination polymers of sodium nitrite and hydrogen peroxide detection has high and low detection limits, the detection sensitivity and minimum detection limit for performance evaluation, the best performance of the electrode is Cu 1 Cd 1 TCPP/MWCNTs/GCE electrode, the sensitivity of sodium nitrite and hydrogen peroxide were detected in seven kinds of polymer modified in is the highest,reached 418 mA·M-1. cm-2 and 413.83 mA·M-1. cm-2, and the minimum detection limit of Cu1Cd1TCPP/MWCNTs/GCE in the detection of sodium nitrite in is the lowest,3.2 * 10-6M. It can be seen that in the detection of hydrogen peroxide and sodium nitrite, Cu1Cd1TCPP has the best performance.