Ultrasensitive SERS detection of crystal violet and malachite green based on high surface roughness copper nanocorns prepared via solid-state ionics method

Abstract

Abstract Copper nanostructures with quantum size effect and low preparation cost have broad prospects in detecting signal molecules, conducting films, manufacturing catalysts and improving antibacterial activity. A novel macroscopic dendritic copper nanocorns with the length of 2-50\xa0mm prepared by solid-state ionics method at 8 μA direct current electric field (DCEF) using fast ionic conductor RbCu4Cl3I2 films was reported. The surface-enhanced Raman scattering (SERS) performance of prepared copper nanocorns was detected by crystal violet (CV) and malachite green (MG) aqueous solution as analyte molecules. The results present that many regularly arranged nanoparticles with the diameter from 15 to 40\xa0nm existed on the prepared copper nanocorns, which lead to the nanocorns have high surface roughness. The copper nanocorns contain only Cu elements, no O element and the fractal dimensions of copper nanocorns was 1.411 because of macroscopic dendritic structures. The prepared copper nanocorns composed of pure Cu have high surface roughness and a large number of hot spots formed on the surface of copper nanocorns, so the limit of detection (LOD) for CV and MG detected by copper nanocorns were as low as 1×10-13\xa0mol/L and 1×10-14\xa0mol/L, respectively. The centimeter-scale and high surface roughness copper nanocorns with high purity copper, simple detection procedure, low LOD of analyte molecules and facile material synthesis have strong application prospect in detection of harmful additives in food.