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Real-Time Sensing of O-Phenylenediamine Oxidation on Gold Nanoparticles.

ABSTRACT: Real-time monitoring of chemical reactions is still challenging as well as important to study reaction mechanisms and reaction kinetics. Herein, we demonstrated the real-time monitoring of o-phenylenediamine (OPD) oxidation on the surface of gold nanoparticles by surface-enhanced Raman spectroscopy (SERS). The oxidation mechanism and the reaction kinetics were investigated on the basis of the SERS spectrum variation and the related density functionalized theory calculation. It was shown that the oxidation of OPD in the presence of copper ions was a two-step process of the deprotonation of the amino group on the aromatic rings and the rearrangement of the electron cloud to a π-conjugated system, which may open a new door to comprehensively understand the reaction process.

SUBMITTER: Yu RJ

PROVIDER: S-EPMC5375816 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Real-Time Sensing of O-Phenylenediamine Oxidation on Gold Nanoparticles.

Yu Ru-Jia RJ Sun Jia-Jia JJ Song Heng H Tian Jing-Zhi JZ Li Da-Wei DW Long Yi-Tao YT

Sensors (Basel, Switzerland) 20170307 3

Real-time monitoring of chemical reactions is still challenging as well as important to study reaction mechanisms and reaction kinetics. Herein, we demonstrated the real-time monitoring of o-phenylenediamine (OPD) oxidation on the surface of gold nanoparticles by surface-enhanced Raman spectroscopy (SERS). The oxidation mechanism and the reaction kinetics were investigated on the basis of the SERS spectrum variation and the related density functionalized theory calculation. It was shown that the ...[more]

PMID: 28272329

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