Preparation of polypyrrole-coated silicon nanoparticles

Silicon (Si) nanoparticles were stabilized by sodium dodecyl sulfate and poly(N-vinylpyrrolidone) in water, and coated with polypyrrole (PPy) via in situ polymerization of pyrrole with FeCl3. TEM images revealed that the Si nanoparticles were successfully coated with PPy (average thickness, ∼2 nm). The Li/PPy-coated Si electrode exhibited improved discharge capacities, compared to that of a reported Li/pure Si electrode, even though the capacity fading problem caused by large-scaled crumbling of the electrode was not overcome.