One-pot fabrication of uniform polypyrrole/Au nanocomposites and investigation for gas sensing

A facile one-pot strategy is developed to fabricate polypyrrole (PPy)/Au nanocomposites, in which Au nanoparticles with an average size of ca. 4.2 nm are uniformly dispersed on PPy. The morphology, structure, and composition of the products were characterized by transmission electronic microscopy, X-ray powder diffraction, X-ray photoelectron spectroscopy and thermogravimetric analysis. Lysine plays a crucial role in the formation of uniform PPy/Au nanocomposites. Importantly, the PPy/Au nanocomposites have demonstrated great potential for detecting ammonia gas at room temperature, showing enhanced sensor performances in comparison to pure PPy as a result of the funtionalization of Au nanoparticles on PPy. The possible sensing mechanism is also discussed.