Fabrication and Application of Ag@SiO/Au Core-Shell SERS Composite in Detecting Cu in Water Environment.

A sensitive and simple method for detecting Cu in the water source was proposed by using surface-enhanced Raman scattering spectroscopy (SERS) based on the Ag@SiO/Au core-shell composite. The Ag@SiO SERS tag was synthesized by a simple approach, in which Ag nanoparticles were first embedded with Raman reporter PATP and next coated with a SiO shell. The Ag@SiO nanoparticles had strong stability even in a high-concentration salty solution, and there were no changes to their properties and appearance within one month.