▎ 摘　　要

A fast and green way to synthesize a free-standing and flexible silver nanoparticles-graphene (Ag NPs-GE) film with high surface-enhanced Raman scattering (SERS) sensitivity has been developed. The silver nitrate-graphene oxide (Ag+-GO) films can be fabricated through vacuum filtration of the Ag+-GO suspension. And then, through the thermal annealing under H-2/Ar atmosphere at 400 degrees C, as-synthesized Ag+-GO films were thermal reduced to Ag NPs-GE films. The SERS activity of these substrates was greatly influenced by different laser wavelengths. And the maximum enhancement factor value for the Raman signals of R6G adsorbed on Ag NPs-GE substrate obtained at 780 nm (1.25 x 10(7)) was much larger than that acquired at 532 nm (3.7 x 10(5)). Furthermore, the high mechanical and flexibility of the GE sheets can provide protection of Ag NPs from the surrounding environment to yield a high degree of temporal stability.