Conductive polyaniline (PANT) nanotubes were synthesized by the vapor phase polymerization of aniline monomers using hausmannite Mn3O4 nanofibers as an oxidant. Fibrous Mn3O4 templates with an average diameter of 57 nm were prepared by the calcination of electrospun composite nanofibers of polyvinylpyrrolidone and manganese(II) acetate. The enhanced nanotube formation in the presence of H2SO4 was interpreted as the growth of a very thin (similar to 15 nm) PANT sheath layer on the nanofiber template at the sacrifice of the core Mn3O4 oxidant in the gas phase. The significant conductivity of the PANI nanotube mat was correlated to the favorable formation of anion-doped PANI confirmed by XPS. (C) 2014 Elsevier B.V. All rights reserved.