Nano-Fe3O4-loaded tubular carbon nanofibers (nano-Fe3O4/TCNB) were synthesized by adding TCNFs into the high-temperature solution-phase reactions of iron(III) acetylacetonate with 1,2-hexadecanediol in the presence of oleic acid and oleylamine. The morphology and structure of this material were investigated by transmission electron microscopy (TEM) and X-ray diffraction (XRD) measurements. TEM observation clarified that nano-sized Fe3O4 particles with a uniform diameter of several nanometers were distributed and loaded tightly on the TCNF surfaces (inside and outside). After being annealed at 500 degrees C in Ar gas flow, nano-Fe3O4/TCNFs were used as the active material of negative electrodes for Fe/air batteries. Using an alkaline aqueous electrolyte with K2S additive, a high specific capacity of 786 mAh g(-1) and cycling efficiency of 76% at the 30th cycle were obtained. The downsizing of the conductive Fe3O4 nano-particles was considered to have contributed to the good electrochemical properties of the material. (C) 2011 Elsevier B.V. All rights reserved.