Studies On Anion-Selective Electrodes Based On Symmetrical And Unsymmetrical Schiff Based Organic Metallic Complexe As Neutral Carrier

The ion-selective electrode, as one of the most important groups of chemical sensors, is characterized as simple in preparation and robust in operation, which can carry out rapid determination of sample continuously. And it doesn't determine concentration of ion, but activity of ion, which is very important in environment and biological sample analysis. The design, synthsis and application of new sensor materials, in particular new selective carriers are not only main research aspects for the ISE but also central issues in modern chemistry. Recently, study on the ISEs with anti-Hofmeister selectivity pattern is an important and interesting subject in the field of electrochemistry and electroanalytical chemistry. The present work focuses on the search for design and synthsis of new metallic complexes and basic studies on the solvent polymeric membrane (SPM) anion-selective electrodes containing the novel metallic complexes as neutral carrers. The electrodes can be applied to the analysis of samples of waste water, medicine and so on.The main contents and some conclusions of the thesis are as follows:1. Studies on asymmetrical tetradentate Schiff base mononuclear cobalt(â…¡), copper(â…¡) , mercury(â…¡) complexes as neutral carriers for the thiocyanate-selective electrodeO-hydroxybenzophenone-1,2-diaminobenzene-pyrrole-2-carbaldehyde(H₂L) mono-nuclear cobalt (â…¡), copper(â…¡), mercury(â…¡) complexes were designed, synthesized and used as neutral carriers to prepare anion selective electrodes and their anion response characteristics were investigated for the first time. The results show that the proposedelectrode with the Cu(II)-chelate demonstrates an anti-Hofmeister selectivity sequence with a high selectivity towards thiocyanate, a wide linear range, a low detection limit and a fast response time over the entire concentration series. The response mechanism was also discussed "by use of impedance and spectroscopic techniques and the influence on the electrode performances by lipophilic charged additives. The preliminary application of the electrode to the determination of thiocyanate in wastewater and urine samples gave the results with which are in good agreement those given by HPLC method.2. Studies on a highly iodide-selective electrode based on unsymmetrical tetradentate Schiff base binuclear mercury (II) complex as neutral carrierA few binuclear metal chelates of unsymmetrical tetradentate Schiff base, 2,2-bis(pyrrole-2-carbaldehyde-o-phenylenediamine)-methylene-bis(4,4-salicylaldeh yde), [M(II)2-BPPM] (M=Cu, Hg, and Co), were designed and synthesized. Meanwhile, symmetrical tetradentate Schiff base binuclear mercury(II) complex, 2,2 -bis(salicylaldehyde-o-phenylenediamine)-methylene-bis(4,4 -salicylaldehyde) binuclear mercury(II) [Hg(II)2-BSPM], was also synthesized so as to prepare anion selective electrodes. The comparison between potentiometric response behavior towards anions of the membrane electrodes based on the two symmetrical and unsymmetrical tetradentate Schiff base binuclear mercury(II) complexes were studied. The results show that the membrane electrodes incorporating the complex [Hg(II)2-BPPM] rather than [Hg(II)2-BSPM] offer substantially improved potentiometric response characteristics towards iodide. The selectivity sequence obtained obviously deviated from Hofmeister pattern: iodide > salicylate > perchlorate > thiocyanate > nitrite > bromide > nitrate > chloride > sulfite > sulfate. The electrode is applied to the determination of iodide in wastewater from our laboratory and Jialing River and the results are satisfactory.3. Studies on thiomacrocyclic Schiff base complexes of binuclear copper(II) and binuclear mercury(II) as neutral carriers for preparation of the highly salicylate-selective electrode and the iodide-selective electrode respectivelyThiomacrocyclic Schiff base complexes of binuclear copper(II) and binuclear...