In situ surface-enhanced Raman spectroscopy study of interfacial catalytic reaction of bifunctional metal nanoparticles

Metal-semiconductor bifunctional core-shell nanomaterials were studied using catalytic system Au@CdS as example that displayed surface plasmon resonance (SPR) effects and photocatalytic activity. Some mechanisms of photocatalytic activity of the studied nanomaterials were discussed. Surface-enhanced Raman spectroscopy (SERS) was used to monitor in situ the SPR-driven photocatalytic dimerization of 4-nitrothiophenol (pNTP) to 4,4′-dimercaptoazobenzene (DMAB). The transfer path of “hot” electrons in Au@CdS was tracked by monitoring Raman spectral changes of the probe molecule. Nanomaterials Au@CdS showed high catalytic activity in photocatalytic degradation of rhodamine 6G. The SPR-displaying metal-semiconductor nanocomposite was indicated to be an extremely promising photocatalytic and in-situ SERS probe.