Study Of Electrochemical Sensing Based On Materials Of Nano-mentallic Oxide

Nano-mentallic oxide has possessed the unique structure, which results in series of special properties. So the application of nano-mentallic oxide materials has widely involved in nanoelectronics, catalysis, environmental detection, electrochemical sensor and so on. This thesis is aim to nano-mentallic oxide materials(zirconia nanoparticles and titanium dioxide nanotube arrays), and develops electrochemical sensor of high sensitivity and selectivity in order to detect biomolecular, environmental pollutions and food additives. The thesis can be divided into three chapters.Chapter I: we have successfully developed a novel photoelectrochemical glucose sensor based on nanocomposites of Au nanoparticles/Cu S nanoparticles/Ti O2 nanotube arrays(Au NPs/Cu S NPs/Ti O2 NTs). Highly ordered Ti O2 NTs were prepared by anodization, Cu S NPs and Au NPs were successively deposited on Ti O2 NTs by successive ionic layer adsorption and reaction method. The results showed that this sensor was found to exhibit remarkable photocurrent signal in process of detection glucose, photocurrent and concentration of glucose have linear relationship in range from 1.0×10-9 mol/L to 3.0×10-8 mol/L, a limit of detection as low as 0.3×10-9 mol/L(S/N=3), and good selectivity, acceptable reproducibility and stability.Chapter II: we have successfully developed a novel methyl parathion(MP) electrochemical sensor based on nanocomposites of zirconia/ordered macroporous polyaniline(Zr O2 NPs/OMP) by electro-polymerization and electro-deposition. The results showed that this sensor was found to exhibit remarkable current signal in process of detection MP, current signal and concentration of MP have linear relationship in two concentration range from 5.96×10-10 mol/L to 3.45×10-9 mol/L and from 3.45×10-9 mol/L to 1.02×10-8 mol/L, a limit of detection as low as 2.28×10-10 mol/L(S/N=3), and good selectivity, acceptable reproducibility and stability. Finally, this novel sensor could be successfully applied to detect MP in real samples of apple and cabbage.Chapter III: we have successfully developed a novel nitrite electrochemical sensor based on nanocomposites of zirconia/reduced graphene oxide(Zr O2/r GO) by electro-deposition. The results showed that this sensor was found to exhibit remarkable current signal in process of detection nitrite, current signal and concentration of nitrite have linear relationship in two concentration range from 3.0×10-7 mol/L to 1.0×10-6 mol/L and from 1.0×10-6 mol/L to 6.0×10-6 mol/L, a limit of detection as low as 1.0×10-7 mol/L(S/N=3), and good selectivity, acceptable reproducibility and stability.