Reversibly Modulating Plasmon-mediated Chemical Reaction via Electrode Potential on Reliable Copper Nanoelectrode

Plasmonic metal nanostructures are essential for plasmon-mediated chemical reactions (PMCRs) and surface-enhanced Raman spectroscopy (SERS). The nanostructures are commonly made from the coinage metals gold and silver. Copper (Cu) is less used mainly due to the difficulties in fabricating stable nanostructures. However, Cu is an attractive option with its strong plasmonic properties, high catalytic activities, and relatively cheap price. Herein, we fabricated tunable, reliable, and efficient Cu nanoelectrodes (CuNEs). Using time-resolved electrochemical SERS, we have comprehensively studied the reversible chemical transformations between aromatic amine and nitro groups modified on the CuNE surface. Their PMCRs are well-controlled by changing the surface roughness, the oxidation states of Cu, and the applied electrode potential. We thus demonstrate that the Cu nanostructures enable better investigations in the interplays between PMCR, electrochemistry, and Cu catalysis.

Automated summary

In this study, tunable, reliable, and efficient copper nanoelectrodes (CuNEs) were successfully fabricated, and the reversible chemical transformations between aromatic amine and nitro groups on the CuNE surface were comprehensively studied using time-resolved electrochemical surface-enhanced Raman spectroscopy. It was found that the plasmon-mediated chemical reactions (PMCRs) of CuNEs could be well-controlled by changing the surface roughness, oxidation states of copper, and the applied electrode potential. This study demonstrates the importance of Cu nanostructures in investigations of the interplays between PMCR, electrochemistry, and Cu catalysis.