Effects Of The Composition And Shape Of Au-Based Nanoparticles On Detection For Hydrogen Peroxide

Hydrogen peroxide?H₂O₂?is a strong oxidant and has disinfection,sterilization,bleaching and so on.So it is widely used in production and storage processes of food,health products and its raw material.However,the hydrogen peroxide also does harm for health,such as inducing cancer,accelerating ageing and causing cardiovascular disease.Therefore,the research and developing of the fast detection methods for hydrogen peroxide are significant interest in the theoretics and practical application.In this thesis,we synthesized a series of Au-based nanoparticles?NPs?and constructed electrodes modified by them,and investigated the effects of the morphology and composition of the NPs on the detection for hydrogen peroxide.? Spherical Au nanoparticles?Au-NPs?with the average size of 5±1nm and face-centred cubic?fcc?structure were synthesized via reverse microemulsion method.The Au-NPs/HRP/GCE electrode of H₂O₂ sensor was modified by as-prepared Au-NPs.Cyclic voltammetry?CV?and chronoamperometry?i-t?curves were employed to study the performance of Au-NPs/HRP/GCE towards detecting H₂O₂.In the test range,the results showed that there were linear relationship?R2=0.99884?between the response current and the concentration of H₂O₂,and the detection limit of H₂O₂ was 3.2×10^-6 mol/L?s/n=3?.? Networked Au nanoparticles?Au-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 Au-NTs/HRP/GCE electrode.Using the CV and i-t methods,the performance of Au-NTs/HRP/GCE towards detecting H₂O₂ was investigated.In the test range,the results showed that the modified sensor electrode of Au-NTs with a large number of surface defects showed much better detection performance of the hydrogen peroxide.There were linear relationship?R2 =0.99920?between response current and the concentration of the hydrogen peroxide.The detection limit was 1.7×10-7 mol/L?s/n=3?.? Decahedral AuCu nanoparticles?AuCu-NPs?with fcc structure were synthesized via reverse microemulsion method.The AuCu-NPs/HRP/GCE electrode of H₂O₂ sensor was modified by the as-prepared AuCu-NPs.CV and i-t curves were employed to study the performance of AuCu-NPs/HRP/GCE electrode towards detecting H₂O₂.In the test range,the results showed that there were linear relationship?R2 =0.99863?between response current and the concentration of the hydrogen peroxide.The detection limit was 7.5×10^-6 mol/L?s/n=3?.? Icosahedral AuFe nanoparticles?AuFe-NPs?with fcc structure were synthesized via reverse microemulsion method.The AuFe-NPs/HRP/GCE electrode of H₂O₂ sensor was modified by the as-prepared AuFe-NPs.CV and i-t curves were employed to study the performance of AuFe-NPs/HRP/GCE electrode towards detecting H₂O₂.In the test range,the results showed that there were linear relationship?R2 =0.98366?between response current and the concentration of the hydrogen peroxide.The detection limit was 5.7×10-5 mol/L?s/n=3?.? Agglomerates of AuPd nanoparticles?AuPd-NPs?with fcc structure and large number of surface defects were synthesized,and it was used for modifying electrode of H₂O₂ sensor and constructing AuPd-NPs/HRP/GCE electrode.Using the CV and i-t methods,the performance of AuPd-NPs/HRP/GCE towards detecting H₂O₂ was investigated.In the test range,the results showed that there were linear relationship?R2 =0.99501?between response current and the concentration of the hydrogen peroxide.The detection limit was 2.1×10^-6 mol/L?s/n=3?.