Polyaniline (PANI)/silica hybrid nanofiber webs were prepared by two methods: (1) in situ polymerization of aniline-doped silica nanofibers in ammonium persulfate solution and (2) immersing the silica nanofibers into PANI solution. The PANI/silica hybrid nanofiber web had electric conductivity over 10(-4) S/cm. properties of the hybrid web prepared by the in situ polymerization were, on the whole, better than those of prepared by the immersion method. The PANI/silica hybrid nanofibers were characterized with SEM, XRD, TGA, and electrical conductivity. Variation of the electrical conductivity of the PANI/silica hybrid web prepared by the in situ polymerization with the reaction conditions were investigated. (c) 2004 Elsevier B.V. All rights reserved.