Synthesis And Characterization Of AuAg Alloy Nanoparticles On Hydrogen Peroxide Sensor Application

Hydrogen peroxide?H₂O₂?is a strong oxidizing agent,and its content determination has important theoretical significance and practical application value in food detection and other fields.At present,there are many determination methods,and through them,the electrochemical method is widely used in H₂O₂ determination because of its simple method,high sensitivity and strong practicability.In this thesis,we synthesized a series of AuAg nanoparticles and constructed electrodes modified by them,and investigated the effects of the morphology and composition of these nanoparticles on the detection for hydrogen peroxide.?Spherical AuAg particles?AuAg-NPs?with the average size of 7.5±0.5nm and face-centred cubic?fcc?structure were synthesized via reverse microemulsion method at room temperature,and using potassium borohydride as reducing agent;Spherical AuAg particles?AuAg-NPs?with the average size of 4.5±0.5nm and face-centred cubic?fcc?structure were synthesized using hydrazine hydrate as reducing agent.Cyclic voltammetry?CV?and chronoamperometry?i-t?curves were employed to study the performance of AuAg-NPs/HRP/GCE towards detecting H₂O₂.In the test range,the results showed that there were linear relationship?R2=0.9982?between the response current and the concentration of H₂O₂,and the detection limit of H₂O₂ was 2.7×10^-7mol/L.? Networked AuAg nanoparticles?AuAg-NTs?with the fcc structure and large number of surface defects were synthesized,and it was used for modifying electrode of H₂O₂ sensor and constructing AuAg-NTs/HRP/GCE electrode.Using the CV and i-t methods,the performance of AuAg-NTs/HRP/GCE towards detecting H₂O₂ was investigated.In the test range,the results showed that the modified sensor electrode of AuAg-NTs with a large number of surface defects showed much better detection performance of the hydrogen peroxide.There were linear relationship?R2=0.9852?between response current and the concentration of the hydrogen peroxide.The detection limit was 7.2×10^-8 mol/L.? Spherical AuAgCu nanoparticles?AuAgCu-NPs?with fcc structure were synthesized via reverse microemulsion method.The AuAgCu-NPs/HRP/GCE electrode of H₂O₂ sensor was modified by the as-prepared AuAgCu-NPs.CV and i-t curves were employed to study the performance of AuAgCu-NPs/HRP/GCE electrode towards detecting H₂O₂.In the test range,the results showed that there were linear relationship?R2=0.9880?between response current and the concentration of the hydrogen peroxide.The detection limit was 1.6×10^-7 mol/L.