▎ 摘　　要

Controlling the shape of the conducting polymer-noble metal composites is a key factor in determining their properties and applications. In this paper, we demonstrate a novel strategy to fabricate Au-polypyrrole (PPy) composites with unusual morphology using poly(4-vinylpyridine) (P4VP) brush grafted on graphene oxide (GO) as a reaction chamber. When the GO/P4VP brush bearing AuCl4- ions is exposed to pyrrole vapor or directly immersed into pyrrole solution, novel Au-PPy nanotubules and flower-like Au mesoparticles-PPy composites are formed on the surface of GO/P4VP brush, respectively. The application of the as-prepared GO/P4VP/Au-PPy composites in catalysis and surface-enhanced Raman scattering (SERS) are investigated. The relevant results exhibit that the GO/P4VP/Au-PPy nanotubules can act as an efficient catalyst for reduction of 4-nitrophenol, and the GO/P4VP/flower-like Au mesoparticles-PPy composites can be used as a sensor platform for the detection of organic molecules by SERS.