Synthesis of core-shell Au@polypyrrole nanocomposite using a dendrimer-template approach.

Conducting polymeric nanostructures have been reported recently, which were produced from polypyrrole (PPy), including hollow nanocapsules, nanofibers, nanoporous membranes, nanowires, and nanofilms. In most cases, new synthetic routes were used aimed at controlling specific properties of these conducting nanostructures at the molecular level. In this communication we present a new chemical route to synthesize polypyrrole-based nanocomposites, in which polyamidoamine (PAMAM) dendrimers encapsulating Au nanoparticles are used as template. The two-step synthesis comprises the reduction of Au nanoparticles inside PAMAM molecules followed by PPy polymerization around the PAMAM-Au nanoparticles. The structure of the core-shell PAMAM-gold@polypyrrole nanospheres comprises a 40 nm PPy shell enclosing a core of 3 nm gold nanoparticles, as revealed by Transmission Electronic Microscopy (TEM). This new, environmentally-friendly approach may be suitable to produce hybrid nanomaterials for applications in catalysis, batteries, sensors, and micro/nanoelectronic devices.