Study On Surface Plasmon-driven Catalytic Oxidation Reaction Of Aniline Compounds Using SERS Technology

Surface-enhanced Raman scattering(SERS)is widely used in many fields such as chemistry,biology,physics,and materials science because it enhances the inherent low Raman scattering cross section of molecules,even at the single molecule level.SERS has two enhancement mechanisms that are widely recognized.One is the electromagnetic enhancement(EM)mechanism,which is caused by strong surface plasmon resonance excited by incident light on a rough metal surface.The other is a chemical enhanced(CM)mechanism that can be viewed as a resonant Raman process between new excited states caused by charge transfer between the metal surface and the adsorbed molecules.Based on this,we carried out the research work on this subject through SERS technology.We mainly use the SERS technology to monitor the surface plasmon-driven catalytic oxidation reaction.(1)Based on the study of the surface plasmon-driven catalytic oxidation reaction of p-aminothiophenol(PATP),we further explored the effect of different protic solvents on the surface plasmon-driven catalytic oxidation reaction.By comparing the SERS spectra,we found that the rates at which the PATP molecules undergo a plasmon-driven catalytic oxidation reaction in different diol solvents are different.Since the substitution positions of the hydroxyl groups on the carbon chain are different,the collision probability with the hot electrons generated by the plasmon is different.Thus,the remaining holes have different oxidation rates for PATP molecules.Here,we confirmed that in addition to the pH value in the control system,the addition of metal cations and other methods to control the reaction rate,the solvent in the system can also regulate the surface plasmon-driven catalytic oxidation reaction.(2)Through the SERS technique,we studied the surface plasmon-driven catalytic oxidation reaction of ethynylaniline(PEAN)on nanosilver.The experimental results show that PEAN can also undergo a similar surface plasmon-driven catalytic oxidation reaction with PATP under the action of nanosilver.We not only proposed the reaction mechanism of PEAN under plasmon-driven catalytic oxidation reaction,but also further explored the optimal power and exposure time of PEAN dimerization reaction.This work extends the system of surface plasmon-driven catalytic oxidation reaction.Through systematic research of this subject,we not only supplemented the regulation method of plasmon-driven catalytic oxidation reaction of PATP,but also excavated another substance that can undergo surface plasmon-driven catalytic oxidation reaction.