Spectral proof for the 4-aminophenyl disulfide plasma assisted catalytic reaction

Lixin Xia,Jing Wang,Peng Song,Shiwei Wu,Caiqing Ma

doi:10.1038/s41598-017-04658-w

Abstract

4-Aminophenyl disulfide (APDS) forms on the surface of silver nanoparticles due to chemical adsorption and disulfide bond breakage. This leads to the formation of new silver chemical bonds to result in the new compound NH2-C6H6-S-Ag. This novel material produces enhanced Raman spectra under weak laser light irradiation. When irradiated a plasma-assisted catalytic coupling reaction of NH2-C6H6-S-Ag occurs leading to the formation of 4,4-dimercaptoazobenzene (DMAB). Raman spectroscopy was used to monitor this reaction process, showing clear spectral changes associated with each step after addition of Ag nanoparticles onto the APDS powder. This method clearly shows the mechanism of the plasma-assisted catalytic reaction and may also be useful for spectral imaging purposes.

Highlights

Surface enhanced Raman spectroscopy (SERS) is a technique utilized for analysis and testing, and owing to the rapid and simple sample requirements it is employed in a wide range of applications[1,2,3,4,5,6,7]
Aromatic disulfide reversible cross-linked polymers are introduced into systems in the field of intelligent materials[21], for example, Aminophenyl disulfide (APDS) can be used as a reusable handle, as a repairable and recyclable epoxy curing agent network[22], alongside being an important raw material
Our results indicate that when the 633 nm laser was selected as the excitation source, DMAB was quickly generated following mixing PATP with Ag nanoparticles

Summary

Introduction

Surface enhanced Raman spectroscopy (SERS) is a technique utilized for analysis and testing, and owing to the rapid and simple sample requirements it is employed in a wide range of applications[1,2,3,4,5,6,7]. In 2010, the three so-called b2 enhancement peaks expected in the SERS spectrum of 4-aminothiophenol (PATP) were absent, leading to the discovery of a new material, DMAB. This new material forms by a plasma-assisted catalytic coupling reaction under SERS conditions, a process which was later confirmed by experimental and theoretical studies[8, 9]. As changes in the spectra are clearly observed, there action progress can be readily monitored and rationalised This provides a simple and intuitive method for understanding plasma-assisted catalytic reactions and analysing the experimental principles. There are potential applications in molecular detection, experimental monitoring and molecular imaging

Methods

Results

Conclusion