Novel, porous tantalum pentoxide (Ta2O5) nanofibers with 150-250 nm diameter were obtained by high temperature calcination of the as-electrospun tantalum pentoxide/poly(vinyl acetate) (PVAc) composite fibers prepared by sol-gel processing and electrospinning technique. Surface analysis, structure and elemental composition of these as-electrospun and as-calcinated Ta2O5 nanofibers have been studied by scanning electron microscope (SEM) equipped with an energy dispersive X-ray analysis (EDX), high resolution field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), X-ray diffraction patterns (XRD) and FT-IR. High-resolution FE-SEM images showed the porous nature of Ta2O5 nanofibers. EDX analysis revealed the perfect stoichiometry of the nanofibers as Ta2O5. A linear correlation was noted between the calcination temperature and orthorhombic crystalline phase evolution of Ta2O5. (c) 2005 Elsevier Ltd. All rights reserved.