An In-Situ Variable-Temperature Surface-Enhanced Raman Spectroscopic Study of the Plasmon-Mediated Selective Oxidation of p-Aminothiophenol

The roles of temperature change in surface-enhanced Raman scattering (SERS) hotspots are important for understanding the plasmon-mediated selective oxidation of p-aminothio-phenol in a SERS measurement. Here, we demonstrate that the temperature change in hotspots seriously influences the conversion of p-aminothiophenol on Au by employing variable-temperature SERS measurements. The conversion steadily and irreversibly increased when the temperature increased from 100 to 360 K. But the conversion decreased above 360 K, because this conversion was exothermic. This temperature-dependence conversion suggests that the temperature change in hotspots originated from the photothermal effect should be coupled to the hot-electron effect in promoting the selective oxidation of p-aminothiophenol.