Facile synthesis of gold nanoflowers as SERS substrates and their morphological transformation induced by iodide ions

We report a new strategy to prepare gold nanoflowers (AuNFs) using a two-step seed-mediated method. The as-prepared AuNFs were employed as surface-enhance Raman scattering (SERS) substrates, showing strong signal enhancement. We further found that iodide ions (I – ) could selectively induce the morphological transformation of AuNFs to spheres, resulting in a blue-shift of the localized surface plasmon resonance (LSPR) bands, a color change of the AuNFs solution from blue to red, and decreased SERS activity. This behavior allows the AuNFs to be used in the determination of I – .