Facile and green synthesis of SERS active and ferromagnetic silver nanorods

Silver nanorods with increased surface-enhanced Raman scattering sensitivity and detection have been synthesized in a novel, facile, and eco-friendly way through a simple chemical reduction method using 2,3-dihydroxyfumaric acid in aqueous solution under aerobic conditions. The structure and composition of the silver nanorods were characterized by UV/Vis spectroscopy, powder X-ray diffraction, transmission electron microscopy (TEM), and field emission scanning electron microscopy (FESEM). Simple hard washing agglomerates the nanorods. The agglomerated nanorods consist of several "hot spots", easily replaceable capping agents and an anisotropic shape, which are all responsible for its high sensitivity and trace detection (picomolar level) of different adsorbate molecules (thiophenol, Rhodamine 6G) in surface-enhanced Raman scattering. Rarely observed, but theoretically established, unpaired s-electron-based ferromagnetism is the other interesting aspect of these nanorods. We have developed a novel method employing a new reducing agent for the synthesis of silver nanorods having excellent SERS sensitivity and trace detection ofthe adsorbate molecules (thiophenol and Rhodamine 6G) up to picomolar concentrations.