Flower-shaped PdI₂ nanomaterials with remarkable surface-enhanced Raman scattering activity

Uniform dispersed flower-shaped palladium iodide (PdI₂) nanoparticles were prepared successfully by a simple wet chemical method. The as-synthesized products were structurally and morphologically characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), as well as high resolution transmission electron microscopy (HRTEM). Large numbers of twin and stacking faults were observed at the tip of the petals of flower-shaped morphology. At the same time, a series of palladium iodide structures with different morphology and size were obtained through the manipulation of the concentration of KI and the reaction temperature. The formation of typical flower-shaped palladium iodide was correlated with their reaction conditions. The as-produced PdI₂ nanoparticles exhibit high surface-enhanced Raman scattering (SERS) activities for malachite green (MG) probe molecules with 1.0 × 10^-7 M concentration. As a result, the flower-shaped PdI₂ nanostructures coupled with SERS hold a great potential as a rapid and ultra-sensitive agent for detecting trace amounts of prohibited substances in contaminated food samples.