Study of thermoelectric enhanced SERS and photocatalysis with ZnO-metal nanorod arrays

Herein, a thermoelectric induced surface-enhanced Raman scattering (SERS) substrate consisting of ZnO nanorod arrays and metal nanoparticles is proposed. The intensities of SERS signals are further enhanced by an order of magnitude and the limit of detection (LOD) for the molecules is reduced by at least one order of magnitude after the application of a thermoelectric potential. The enhancement mechanism is analyzed carefully and thoroughly based on the experimental and theoretical results, thus proving that the thermoelectric-induced enhancement of the SERS signals should be classified as a chemical contribution. Furthermore, it is proved that the electric regulation mechanism is universally applicable, and the fabricated substrate realizes enormous enhancements for various types of molecules, such as rhodamine 6G, methyl orange, crystal violet, amaranth, and biological molecules. Additionally, the proposed electric-induced SERS (E-SERS) substrate is also realized to monitor and manipulate the plasmon-activated redox reactions. We believe that this study can promote the course of the research on E-SERS and plasmon-enhanced photocatalysts.