Polypyrrole-coated alpha-MoO3 nanobelts with good electrochemical performance as anode materials for aqueous supercapacitors

A nanocomposite of molybdenum trioxide (alpha-MoO3) nanobelts coated with polypyrrole has been fabricated by a simple in situ polymerization route. The structure, morphology and electrochemical performance of the nanocomposite were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and electrochemical measurements. It was found that the polypyrrole acted as a conducting matrix and a coating agent, which effectively improves the conductivity of the MoO3 nanobelts and inhibits the dissolution of molybdenum ions during cycling. The supercapacitor based on the PPy@MoO3 nanocomposite as the anode, activated carbon as the cathode and 0.5 M K2SO4 aqueous solution as the electrolyte exhibits better rate capability as well as excellent cycling performance compared to the virginal MoO3.