Stable zinc anodes by in situ polymerization of conducting polymer to conformally coat zinc oxide particles

Polypyrrole (PPy) was directly synthesized on the surface of zinc oxide (ZnO) particles by in situ polymerization, resulting in a composite material which avoids direct contact with electrolyte and restricts the diffusion of discharge products. The microstructure of polymer-coated ZnO was observed by scanning electron microscopy and transmission electron microscopy (TEM) tests, and TEM image clearly confirms the existence of a thin layer of polymer film (about 10 nm) around ZnO particles. Anodic polarization curves and impedance spectra measurements indicate that PPy-coated ZnO possesses higher electrochemical activity compared with pure ZnO. The electrodes prepared from PPy-coated ZnO exhibit remarkably superior cycle stability, while the blank electrodes without polymer coating suffer from rapid capacity fading.