Synthesis, characterization and electrochemical study of Mn-doped TiO2 decorated polypyrrole nanotubes

Abstract

Nanostructured conductive polymers are the growing interest in the field of electrochemistry due to their superior conductivity and environmental friendliness. The existence of transition metal oxides could improve their nanostructure as well as conductive properties. In this study, polypyrrole nanotubes are synthesized in the presence of TiO2 and manganese (Mn)-doped TiO2 nanoparticles (NPs) to investigate their electrochemical properties. Details characterization of the synthesized composites were done by X-Ray diffraction (XRD) and TEM. The TEM analysis shows that doping of TiO2 with Mn decrease the grain size of the TiO2 nanoparticles and successively its effects on the synthesis of the PPy nanotubes (PPyNTs). TEM confirmed that PPyNTs synthesized in the presence of Mn-doped TiO2 are thinner in size compare to the PPyNTs synthesized in presence of pure TiO2. The electrochemical effectiveness of the synthesized PPy nanocomposite was investigated using cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). CV and EIS both on a modified glassy carbon electrode reveal the better electron transportability for the Mn-doped TiO2 PPyNTs due to the synergistic effect of doping and decreased the size of PPyNTs as well as increased surface area.