Research On Electrochemical Sensors Based On Noble Metal Nanoparticles-two-dimensional Layered Compounds

The dissertation mainly discusses the composite structure sensor based on two-di mensional layer compounds and noble metal nanoparticles for the detection of small m olecules,and briefly introduces two-dimensional layered compounds such as molybde num sulfide and electrochemically reduced graphene oxide,noble metal nanoparticles,such as the use of gold,platinum in the sensor.Taking advantage of the high catalytic performance of two-dimensional layered compounds and the high electron transfer ab ility of noble metal nanoparticles,a sensor with practical value was constructed.Bisph enol A as an endocrine interferon and hydrogen peroxide as a marker for metabolism d etection have great detection significance.The work is mainly divided into three parts.The first work Au-ErGO-ITO electrode is used for the detection of bisphenol A.T he experiment uses electrochemical deposition technology to modify gold nanoparticle s and electrochemically reduced graphene oxide onto ITO,and apply it to the detectio n of bisphenol A.Compared with previous reports,the modification of nanomaterials by electrochemical technology is greener and more efficient,and the modification pro cess is more controllable.At the same time,the trace amount of nano-gold particles att ached to the surface of electrochemically reduced graphene oxide did not interfere wit h the conjugation effect of graphene?-?conjugated structure and bisphenol A.The clu ster is beneficial to the attachment of gold nanoparticles,enhances the electron transfe r ability on the surface of the modification,and improves the current response ability o f the electrode.The experiment explored the reaction process of bisphenol A on the ele ctrode surface by changing the p H environment of the system and studying the kinetic s,and revealed the reaction path of bisphenol A.The Au-ErGO-ITO electrode showed higher sensitivity and higher detection limit for the detection of bisphenol A,but in act ual use,it was found that the traditional sensor had poor selectivity for bisphenol A,so the second work introduced molecular imprinting technology improves its low selecti vity.The second work MIP(BPA-Po-PD)-Au-ErGO-ITO electrode for the detection of bisphenol A,continues the first work,but modified molecularly imprinted membrane on the electrode to improve its ability to select target molecules.Molecularly imprinte d membranes were constructed by hydrogen bonding between the amino group of the more traditional monomer poly-o-phenylenediamine(Po-PD)and the imine group and the hydroxyl group of the template molecule bisphenol A.The experiment optimized t he electropolymerization process of the membrane.By controlling the ratio of templat e to monomer,the number of electropolymerization turns,the elution time and the enri chment time,the molecularly imprinted membrane produced more active sites.The ex periments compared the performance differences between different sensors,and the m olecularly imprinted membrane sensor showed better selectivity.The third work is based on the reduction detection of H₂O₂ by the Pt-Au-Mo S₂-IT O sensor.The experiment uses electrochemical deposition technology to modify gold nanoparticles,platinum nanoparticles and molybdenum disulfide on ITO glass and app ly it to the detection of H₂O₂.Through the optimization of the nanomaterial modificati on process,the modification method of the substrate material was determined.Molybd enum disulfide nanomaterials exhibit high catalytic ability due to their unique edge de ficient sites,and gold and platinum nanoparticles enhance the surface electron transfer ability,thereby constructing sensors with practical value.