Wire-in-tube and tube-in-tube structures have been prepared using single-spinneret electrospinning method through adjusting the preparation parameters of precursors and subsequent calcined process. Cobalt ferrite (CoFe2O4) samples revealed wire-in-tube morphology using a Co/Fe molar ratio of 1/2. In the case of other a Co/Fe molar ratio, belt and porous fiber morphologies were created. Manganese ferrite (MnFe2O4) sample exhibited tube-in-tube structure while nickel ferrite (NiFe2O4) sample just exhibited tube structure. Because of no template in electrospun polymer composite nanofibers, the precursor diffusion process during calcination plays an important role for morphology controlling. The magnetic properties of samples were examined. The cobalt ferrite (CoFe2O4) wire-in-tube sample revealed the highest saturation magnetization (60 emu/g). After growing with AIOOH on the surface, CoFe2O4 wire-in tube sample revealed a high efficiency for the removal of Congo red pollutant. These nanostructures are particularly attractive for use in the field of nano-fluidic and nano-energy harvesting devices. (C) 2018 Elsevier B.V. All rights reserved.