Copper nanoleaves SERS substrates with high surface roughness for sensitive detection crystal violet and rhodamine 6G

Abstract Copper nanostructures with low preparation cost have become the research hotspot in the fields of optics, electricity, magnetism and so on because of the complementary or higher properties than bulk materials. A novel macroscopic dendritic copper nanoleaves with the length of 3–22 mm prepared by solid-state ionics method at 4 μA direct current electric field (DCEF) using fast ionic conductor RbCu4Cl3I2 films was reported. The surface-enhanced Raman scattering (SERS) performance of prepared copper nanoleaves was detected by crystal violet (CV) and rhodamine 6G (R6G) aqueous solution as analyte molecules. The results present that the leaf width of copper nanoleaves ranged from 2 μm to 5 μm and many regularly arranged nanoparticles with the diameter from 10 to 70 nm existed on the prepared copper nanoleaves, which lead to the nanoleaves have high surface roughness. The copper nanoleaves contain only Cu elements and the fractal dimensions of copper nanoleaves was 1.381 because of macroscopic dendritic structures. The prepared copper nanoleaves composed of pure Cu have high surface roughness and the surface of copper nanoleaves can form a great many of hot spots, so the limit of detection (LOD) for CV and R6G detected by copper nanoleaves were as low as 1 × 10−12 mol/L and 1 × 10−13 mol/L, respectively. The centimeter-scale copper nanoleaves with facile material synthesis, high surface roughness, simple detection procedure and low LOD of analyte molecules have strong application prospect in trace detection of harmful food additives.