SERS Detection Of Diazotization And Azotization Of Aromatic Amine And Its Analytical Application

In recent years,with the continuous development of scientific research,the detection level of ions has also been continuously improved.Detection methods developed based on the different structural properties of different compounds and the differences in chemical properties in the spectrum have gradually entered the public eye.This paper is mainly based on the simple harmonic vibration of different chemical bonds to efficiently detect characteristic ions,and this method of detecting characteristic ions is surface-enhanced Raman spectroscopy（SERS）.SERS technology has been extensively studied in many scientific research fields.People have discovered in their work that the C-H bond,Πbond,and C-C bond on the same aromatic ring all have different simple harmonic vibration modes.Based on this different vibration mode,people have developed a simpler and more convenient analytical method for detecting ions.This thesis is based on the mechanism of organic chemical reactions,and mainly studies the analysis and detection of ions by SERS.Based on the plasmon-catalyzed reaction,the reaction between2,3-diaminopyridine（DAPD）and nitrite ions is mainly studied to produce1H-1,2,3-triazolo[4,5-b]pyridine（TAPD）.Discovered a new enhancement method of DAPD,that is the SERS spectrum of DAPD in a weakly acidic solution containing nitrite ions will show the enhanced Raman characteristic peak of TAPD.Combining the research of organic chemical reaction,the organic chemical reaction of DAPD under acidic conditions was constructed.The product of the reaction will have a characteristic peak at 1336 cm^-1under SERS conditions.According to the relative intensity of the characteristic peaks,a rapid detection method for ferrous ions in the system based on the plasmon catalytic reaction was established.Based on the reaction mechanism of organic chemistry and the characterization method of Raman spectroscopy,the effect of nitrite ion on the Raman spectra of thiophene-3-amine hydrochloride was studied.The experimental results showed that in the acidic solution containing nitrite ions,the Raman spectrum of the product of thiophene-3-amine hydrochloride and nitrite produces a Raman peak at 1260 cm^-1,combined with the results obtained by others Relevant conclusions and research in the field of organic synthesis have determined that the reason for the change in the spectrum is that 3,3-azothiophene is produced by the azo reaction.Further study the mechanism of the reaction,the influence of environmental factors,sample concentration,and other reaction conditions on the conversion of thiophene-3-amine hydrochloride to azothiophene,a method for the analysis and detection of nitrite by Raman technology based on organic synthesis reaction was established.