High-Performance CuSe Nanosheets for Dual-Sensing: HO Electrochemical Detection and SERS Substrate.

A facile fabrication method was developed for the growth of CuSe nanosheets (NSs) on a Cu foil substrate, enabling dual-functionality as an electrochemical sensor for HO and an active surface-enhanced Raman scattering (SERS) substrate. The process involved the preparation of Cu(OH) nanowires (NWs) via electrochemical oxidation, followed by chemical conversion to CuSe through a selenization process. The morphology, composition, and microstructure of the resulting CuSe NSs were systematically characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The CuSe NSs exhibited excellent electrocatalytic activity for HO reduction, achieving a notably low detection limit of 1.25 μM and demonstrating rapid response and high sensitivity with a linear relationship in amperometric detection. Additionally, SERS experiments using Rhodamine B as a probe molecule and the CuSe NS/Cu foil as a substrate displayed outstanding performance, with a detection limit as low as 1 μM. The flower-like structure of the CuSe NSs exhibited linear dependence between analyte concentration and detection signals, along with satisfactory reproducibility in dual-sensing applications. These findings underscore the scalability and potential of this fabrication approach for advanced sensor development.