Reversible Association of Nitro Compounds with p-Nitrothiophenol Modified on Ag Nanoparticles/Graphene Oxide Nanocomposites through Plasmon Mediated Photochemical Reaction.

Because localized surface plasmon resonance in nanostructures of noble metals is accompanied by interesting physical effects such as optical near-field enhancement, heat release, and the generation of hot electrons, it has been employed in a wide range of applications, including plasmon-assisted chemical reactions. Here, we use a composite of silver nanoparticles and graphene oxide (Ag@GO) as the catalytic as well as the analytic platform for plasmon-assisted chemical reactions. Through time-dependent surface-enhanced Raman scattering experiments, it is found that p-nitrothiophenol (pNTP) molecules on Ag@GO can be associated with nitro compounds such as nitrobenzene and 1-nitropropane to form azo compounds when aided by the plasmons. Furthermore, the reaction rate can be modulated by varying the wavelength and power of the excitation laser as well as the nitro compounds used. In addition, the aforementioned coupling reaction can be reversed. We demonstrate that the oxidation of azo compounds on Ag@GO usin...