Selective oxidation etching synthesis of triangular Cu nanoplates with tunable optical properties for SERS analysis

Plate-like metal nanomaterials have attracted much interest due to their anisotropy, high aspect ratio and large surface area. The synthesis of non-noble metal nanocrystals with high purity remains challenging due to the poor regulation mechanism of their seeds, which limits their property and application studies. This paper presents a selective etching mechanism that effectively facilitates the identification and dissolution of non-target seeds during the synthesis of Cu nanoplates. This innovative approach not only enables the production of highly pure nanoplates but also allows for the shape transformation of nanoparticles into nanoplates. The resulting Cu nanoplates exhibit tunable localized surface plasmon resonance (LSPR) characteristics and high enhanced performance in surface-enhanced Raman scattering (SERS). This method offers a novel approach to the synthesis and purification of metal nanocrystals.