Controllable fabrication of SiO2-polypyrrole core-shell dimer and trimer spheres

Core-shell SiO2-polypyrrole (PPy) dimer and trimer particles were prepared using a simple method involving a redox reaction, in which silver nitrate and pyrrole were employed as reactants. The prepared single, dimer, and trimer SiO2 particles, as well as SiO2-PPy core-shell composites, were examined using scanning electron microscopy, high-resolution transmission electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The probable formation mechanism of dimer and trimer core-shell particles was proposed based on the experimental results.