The oxidant and laser power-dependent plasmon-driven surface photocatalysis reaction of p-aminothiophenol dimerizing into p,p'-dimercaptoazobenzene on Au nanoparticles.

Recently, plasmon-driven surface photocatalysis (PDSPC) reactions have attracted more and more attention by means of surface-enhanced Raman scattering (SERS) because we can in situ monitor the reaction process and determine the final products and their quantities by the real-time SERS spectrum. In this work, self-assembly AuNPs with both high catalytic activity and strong SERS effect were used as a bifunctional platform for in situ monitoring of PDSPC reactions. p-Aminothiophenol (PATP), a famous model molecule, was selected as a probe molecule and FeCl3 and NaClO were selected as oxidants. In this way, oxidation reaction of PATP dimerizing into p,p'-dimercaptoazobenzene (DMAB) has been investigated by SERS, and the results show that oxidant and laser power can alter the conversion rate of the reaction. This work provides a novel approach for controlling PDSPC reaction rate, which may be useful for understanding the mechanism of PDSPC reactions.