Surface-enhanced Raman scattering on silver dendrite with different growth directions

A simple and cost-effective strategy was developed to synthesize Ag dendrites via an aqueous chemical route based on spontaneous galvanic displacement between silver (I) ions and copper foil under hydrothermal condition. Ag dendrites with [100], [110], and [111] growth direction can be prepared by adjusting the content of polyvinyl pyrrolidone. The Ag dendrites exhibited fine and well reproducible surface-enhanced Raman scattering effect using Rhodamine 6G as model molecule. There is a corresponding relation between the false color plot of Raman intensity and the dendrite morphology. Among the products, the Ag dendrites growing along [100] direction have the best surface enhancement ability, and a possible explanation was proposed. The results might open up new thinking on surface-enhanced Raman scattering by proper crystal growth and design. Copyright (C) 2011 John Wiley & Sons, Ltd.