| The detection of current signal of parallel catalytic wave was based on oxidation-reduction chemical reaction to make the catalytic current chemically amplified, but the detection of current signal was vulnerable to charging current, interference current of electroactive coexistent matters and electrode pollution effect, which can influence the analytic property of this method, such as sensitivity and reproducibility. And chemiluminescence signal sensing was based on the chemiluminescence reaction to realize luminescence signal sensing without extrinsic excitation light source. Because of no interference stray light, just like background light, rayleigh scattering and raman scattering, and it can also use highly-sensitivity photomultiplier or single photon counting measurement as the detector, so chemiluminescence signal sensing has excellent sensitivity. The combination of the electrochemical parallel catalytic reaction with electrogenerated chemiluminescence analysis, were developed to broaden the analytical application fields of the electrogenerated chemiluminescence analysis.This paper was based on the combination of electrochemical parallel catalytic wave effect and chemiluminescence signal sensing, the time of electrochemical reaction and chemiluminescence reaction of this system was measured, and the possibility of the combination of electrochemical parallel catalytic wave effect with chemiluminescence was also proved. At the same time, a new concept was also proposed for improving the sensitivity of electrochemical analysis ECL analytical characteristics which based on the combination of electrochemical parallel catalytic wave effect and chemiluminesence signal sensing.Two parts are included in the thesis: review and the research paper.In the first part of this thesis, the definition, principle, characteristics of parallel catalytic wave are reviewed. Then, the classification of parallel catalytic wave is mentioned. In addition to these, the research advance of parallel catalytic wave in the electroanalytical chemistry is also given in this part.The second part of this thesis is experiment part, including:â… . The Investigation of a new Analytical Method and Determination of Vanadate (V) based on the Combination of Electrochemical Parallel Catalytic Wave Effect and Chemiluminescence Signal Sensing:It was found that, in the presence of hydrogen peroxide in alkaline medium, vanadate (V) could be reduced at the surface of the graphite electrode, giving parallel catalytic wave effect. Further study indicated that, butyl-rhodamine B can react with the electrogenerated reagent produced through the catalytic reduction of vanadate (V) to the hydrogen peroxide and emit a sensitive CL signal. The electrochemical reaction rate and chemiluminescence reaction rate of this system were measured, and the possibility of the combination of electrochemical parallel catalytic wave effect with chemiluminescence was proved. Based on these findings, a novel electrogenerated chemiluminescence method for the determination of vanadate (V) was developed. At the same time, a new concept was also proposed for improving the sensitivity of electrochemical analysis ECL analytical characteristics based on the combination of electrochemical parallel catalytic wave effect and chemiluminesence signal sensing. Under the optimum experimental conditions , the linear range was 4.0×10-7 mol/L～8.0×10-5 mol/L for vanadate(V). The detection limit was 3×10-8 mol/L.â…¡. Electrogenerated Chemiluminescence (ECL) Determination of Vanadate(V) at Zirconia nanowires-Nafion Modified Graphite Electrode:Compared to bare graphite electrode, vanadate(V) can be selectively separation and enrichment on the Zirconia nanowires-Nafion modified electrode. In the presence of potassium periodate in alkaline medium, vanadate (V) could be reduced at the surface of the modified electrode, giving parallel catalytic wave effect, vanadate (V) can be generated vanadate (II) on the surface of the modified electrode by the electrochemical reduction, vanadate (II) can easily enhance the ECL intensity of butyl-rhodamine B-potassium periodate. In addition, the rate constant of this electrochemical reaction k0 was investigated and confirmed that the speed of electrochemical reaction was in accordance with the subsequent fast CL reaction. Meanwhile, the possibility of the combination of electrochemical parallel catalytic wave effect with chemiluminescence was proved. Based on these findings, a new sensitive ECL method for detecting vanadate (V) was developed. Under the optimum experimental conditions, the ECL intensity was linear with the concentration of vanadate (V) in the range of 2.0×10-12 mol/L～2.0×10-10 mol/L. The detection limit was 8×10-13 mol/L. |
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