Silver Nanoparticles As Photocatalysts Toward Photocatalysis Of Titanium Dioxide And As Electrocatalysts Toward Glucose Oxidation Reaction

Metallic nanomaterials are a new kind of nanoscale materials whose different microstructures result in the great variations in properties.Compared with traditional materials,metallic nanomaterials have better performance in physical detection,chemical catalysis,biological sensing,medical engineering and other fields.At present,although metallic nanomaterials have been widely used in practice,with the in-depth research in this field.the development of relevant disciplines and the progress of detection methods,there is still a great potential for the application of metal nanomaterials to be developed.Silver nanoparticles are a kind of important metal nanomaterials.Silver nanoparticles with tip structure have unique optical properties because of local surface plasmon resonance effect(LSPR).The excellent conductivity of silver nanoparticles makes it of great research and application value in electrochemical reaction and sensor preparation.This paper is mainly divided into three parts.In the first part,silver nanoparticles of various sizes and shapes were prepared by chemical reduction method and added with reducing agent sodium borohydride(NaBH4)in different ways,which were divided into multi-step method and one-step method.In the second part,the process of silver nanoparticles assisting TiO2 photocatalytic reaction was studied with methylene blue solution as the target degradant,and the properties and photocatalytic mechanism of Ag-Ti02 nanocomposites were discussed in depth.In the third part,silver nanoparticles prepared by one-step method are used as raw materials to prepare nano-silver electrodes,study their catalytic effect on glucose oxidation reaction(GOR),and finally prepare glucose sensors.The experimental results show that the spherical Ag nanoparticles and the triangular Ag nanoparticles(Ag nanoprisms)have different particle size distributions and different resonance modes showed in the ultraviolet-visible absorption spectrum.Their colors also distinct a lot at the macro-level.The degradation rate of Ag-TiO2 nanocomposites on methylene blue solution can be as high as 95.21%,which is much higher than that of TiO2(about 50%).In the experiment of electro-catalysis on GOR,the current density will change correspondingly with the change of glucose concentration.The fitting factor R2 of the fitting curve reaches 0.9972,showing a high linear correlation.This shows that the glucose sensor has good performance.