A facile and effective procedure for the preparation of poly(divinybenzene-co-chloromethylstyrene) (poly(DVB-co-VBC)) nanotube/Au-Ag nanoparticle composite (NT-Im-Au-Ag) via using covalently attached imidazolium as linkers was reported. The approach involves the surface functionalization of poly(DVB-co-VBC) NTs with imidazolium cation, anion-exchange with Au precursor (HAuCl4) and followed by the reduction of metal ions. The obtained NT-lm-Au nanoparticle composite was further used as the seeds to produce NT-Im-Au-Ag nanoparticle composite. The morphology and optical properties of the produced nanohybrids were characterized by transmission electron microscopy (TEM), energy dispersive X-ray (EDX) spectroscopy. The as-prepared NT-Im-Au-Ag nanohybrids show an extremely suitable substrate for surface-enhanced Raman spectroscopy (SERS) with a high enhancement factor of 6.7 x 10(7), enabling the detection of 10(-12) M Rhodamine 6G solution. The catalytic performance of NT-Im-Au-Ag nanohybrids was studied by the reduction of 4-nitrophenol with NaBH4 as a reducing agent. Their reaction rate constant was calculated according to the pseudo-first-order reaction equation. (C) 2014 Elsevier B.V. All rights reserved.