| Chemically modified electrodes are of an important branch of electroanalyticalchemistry field in recent years, it has been widely used in basic research, biologicalelements detection, clinical, and environmental protection. With the features of small size,large specific surface area and more active sites, nanomaterials provide a new thought forthe research of chemically modified electrodes. The rapid development of nanomaterialsis of significant value to the prepared of novel chemical modified electrodes. Kinds ofmaterials applied to prepared chemical modified electrodes, polynuclear metalhexacyanoferrate had been received extensive attention of electrochemical analysts dueto their excellent chemical and electrochemical stability, they been extensive researchedfor the applications in electrocatalysis, ionic selective electrode, electrochemical sensors,electrochromism, ionic identification and so on. In view of analytical chemistry, itconstructs excellent sensing interface of the modified electrode for enlarging theirapplication in electrochemistry and electroanalytical chemistry. My thesis mainlytargeted at the utilization of novel polynuclear metal hexacyanoferrate and enlarging theiranalytical performance in electrocatalysis and electrochemical biosensors fields. In thedissertation, five nanomaterials composites including novel nano-NiHCF, nano-PB,nano-Co/CuHCF, nano-Co/FeHCF, nano-Co/FeHCF/CNT were prepared on carbonceramic composite electrodes （CCE） by using electrochemical methods. Theirelectrochemical characterization and electrocatalytic activity were investigated in carefully. In my thesis, methods of excellent determination of hydrogen peroxide andhydrazine were also established in my research work.This dissertation mainly improved stability and electrocatalytic activity of polynuclearmetal nano-hexacyanoferrate and enrichment kinds of polynuclear metalhexacyanoferrate, exploiting them in electrocatalysis and electrochemical biosensorsfields. The main contents were described as follows:1. Plicate poly（p-aminobenzene sulfonic acid） modified electrode （PASA/CCE） wasfabricated by electrochemical methods in PBS containing p-aminobenzene sulfonic acidelectrolytic solution. PASA/CCE and Nano-PB/CCE were deposited on the surface ofPASA/CCE by using electrochemical methods from the buffer solution containingmetallic ion and K3Fe（CN）6. The electrochemical behavior and electrocatalytic activity ofthe resulting two kinds of modified electrode （Nano-NiHCF/PASA/CCE andNano-PB/PASA/CCE） were also investigated carefully. The experimental results showedthat two kinds of modified electrode exhibited high electrocatalytic activity and stability.The Nano-NiHCF/PASA/CCE showed excellent electrocatalytic activity for hydrazine, alinear dependence of the catalytic current versus the concentration of hydrazine wasobtained in the range of5.0×10-7to2.0×10-3mol·L-1with a detection limit of1.0×10-7mol·L-1, and a sensitivity of159.2μA·mM-1. The Nano-PB/PASA/CCE showedexcellent electrocatalytic activity for hydrogen peroxide, a good linear dependence of thecatalytic current versus the concentration of hydrogen peroxide was obtained in the rangeof2.0×10-7to1.2×10-4mol·L-1with a detection limit of4.0×10-8mol·L-1, and asensitivity of589.3μA·mM-1.2. Both of Nano-Co/FeHCF and Nano-Co/CuHCF composite film modified CCE wastypically fabricated containing Co2+, Fe3+, K3Fe（CN）6and containing Co2-, Cu2+,K3Fe（CN）6using two-steps electrochemical method. The electrochemical behavior andelectrocatalytic activity of two kinds of modified electrode were also investigatedcarefully respectively. The results showed the Co/FeHCF, the Co/CuHCF were thematerials that wasn’t seem to be a simple mixture of hexacyanoferrates of both metals ions, insteads of both metals ions occupy certain position lattice each other. Comparedwith single metal hexacyanoferrates electrodes, the Co/FeHCF/CCE andCo/CuHCF/CCE showed high electrocatalytic activity toward the reduction of hydrogenperoxide and toward the oxidation of hydrazine. The linear range of detecting hydrogenperoxide was over the range of5.0×10-7to3.7×10-3mol·L-1with a detection limit of2.0×10-7mol·L-1, and the sensitivity to hydrogen peroxide reduction was44.5μA(mmol·L-1)-1and a good linear behavior was obtained in the range of hydrazine was4.6×10-6to4.4×10-2mol·L-1with a detection limit of2.0×10-7mol·L-1, and thesensitivity to hydrazine oxidation was143.1μA(mmol·L-1)-1respectively.3. Carbon nanotube modified electrode （CNT/CCE） was fabricated by carbonnanotube being dispersed on the surface of CCE. Co/FeHCF/CNT composite modifiedelectrode was prepared in Co2+, Fe2+and K3Fe（CN）6mixed solution by electrochemicaldeposited and characterized with cyclic voltammetry and scanning electron microscope.Its electrochemical characterization and electrocatalytic activity were also researchedcarefully, investigation of electrochemical probe of hydrazine. The experimental resultexhibits that the modified electrode showed excellent electrocatalytic activity toward theoxidation of hydrazine. On the best conditions, the linear range of detecting hydrazinewas2.0×10-72.7×10-4mol·L-1with a sensitivity of774.5μA·(mmol·L-1)-1anddetection limit （3sb, n=11） of4.0×10-8mol·L-1. The proposed method was applied todetect hydrazine in stimulant sample. |
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