Silver/silicon nanostructure for surface-enhanced fluorescence of Ln 3+(Ln=Nd, Ho, and Er)

The surface-enhanced fluorescence of lanthanide ions (neodymium ions Nd³⁺, holmium ions Ho³⁺, and erbium ions Er³⁺) owing to resonant plasmons oscillation on the surface of Ag/Si nanostructure was described. In the presence of Ag/Si nanomaterials, the fluorescence peaks were significantly enhanced, which resulted in a typical 185-fold enhancement at 592 nm for Nd³⁺, 82-fold at 550 nm for Ho³⁺, and 80-fold at 533 nm for Er³⁺ at the concentration of 0.05 M. This Ag/Si nanostructure had larger enhancement factor than that caused by unsupported Ag nanoparticles, which might be attributed to the local field overlap originated from the closed and fixed Ag nanoparticles on silicon nanowires. © 2010 American Institute of Physics.