During the last decade, the electronic conducting polymers have received a great deal of attention because of their remarkable physical, chemical and structural properties. Among them, polypyrrole (PPy) has been attracted special interest because of its high electrical conductivity, environmental stability and favorable physicochemical properties. PPy is usually synthesized by chemical oxidation or electrochemical polymerization of pyrrole (Py) in aqueous media or in various organic solvents, and coarse materials with wide size distribution are often obtained. In this work, we developed a facile method with FeCl₃ oxidant and PVA stabilizer to prepare PPY nanoparticles in a controllable way. Several critical reaction parameters such as the amount of oxidant and stabilizer, the ratio of oxidant to pyrrole, the reaction temperature and time, et al, have been optimized and determined. Monodispersed and size tunable PPY nanoparticles have been synthesized and characterized (as the typical SEM image shown in Fig.1(a)), and their electrochemical capacitive properties have been measured (as the typical charge-discharge curves shown in Fig.1(b)), to understand the size effects of PPY nanoparticle on its capacitive performance. 

Fig.1 (a) SEM image of PPy nanoparticles; (b) Charge-discharge curve of PPY nanoparticles.

Acknowledgements: This work was supported by the National Natural Science Foundation of China (No. 51372178) and the Natural Science Foundation for Distinguished Young Scholars of Hubei Province of China (No. 2013CFA021).