In situ Activation of Thick-film Disposable Copper Electrodes for Sensitive Detection of Malachite Green Using Electrochemical Surface-enhanced Raman Scattering (EC-SERS)

Abstract

In this work, disposable thick-film copper electrodes were used for the detection of malachite green by Electrochemical Surface-Enhanced Raman Spectroscopy (EC-SERS). In situ real-time SERS detection of malachite green was performed during the activation of copper electrodes by voltammetry. This time-resolved method allowed to find dynamically the optimal potential where the detection sensitivity is increased. Scanning electron microscopy images showed that the generation of new fresh copper nanoparticles are responsible to produce the SERS enhancement. A fast decrease of the SERS signal was observed when the potential was shifted from the optimal potential, which could be due to surface changes on the copper electrode. This fact demonstrates the importance of recording the SERS signal in situ and dynamically to obtain the most sensitive method. The combination of in situ time-resolved EC-SERS with disposable, cost-effective screen-printed electrodes leads to a very appropriate method for the sensitive and fast detection of malachite green.