Decoding the Kinetic Limitations of Plasmon Catalysis: The Case of 4-Nitrothiophenol Dimerization
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mechanism is not well understood. In particular, the relative importance of plasmon-generated hot charges and
photoheating are strongly debated. In this article, we evaluate the influence of microscopic photoheating on the kinetics of
a model plasmon-catalyzed reaction: the light-induced 4-nitrothiophenol (4NTP) to 4,4’-dimercaptoazobenzene (DMAB)
dimerization. Direct measurement of the reaction temperature by nanoparticle Raman-thermometry demonstrated that
the thermal effect plays a dominant role in the kinetic limitations of this multistep reaction. On the same time, no reaction
is possible by dark heating to the same temperature. This shows that plasmon nanoparticles have the unique ability to
enhance several steps of complex tandem reactions simultaneously. These results provide insight into the role of hot
electron and thermal effects in plasmonic catalysis of complex organic reactions, which highly important for the ongoing
development of plasmon based photosynthesis.