Silver–polypyrrole composites: Facile preparation and application in surface-enhanced Raman spectroscopy

A facile method to prepare silver–polypyrrole composite (Ag–PPy) by a modified silver mirror reaction is reported. PPy films pretreated by Al(NO3)3 solution were immersed into the silver ammonia with glucose. Silver ammonia ions were reduced to two-dimensional staggered silver nanosheets which immobilized on the surface of polypyrrole. The silver nanosheets with different morphologies and sizes can serve as active-substrates for surface-enhanced Raman spectroscopy (SERS). Using 4-mercaptopyridine (4-Mpy) as probe molecules, the as-prepared composites exhibited excellent surface-enhanced Raman scattering.