Manganese oxyborate (Mn2OBO3) necklace-like nanofibers have been successfully synthesized by an electrospinning technique. First, poly(vinyl pyrrolidone) PVP/[Mn(CH3COO)2 + H3BO3] composite fibers (average size of 300 +/- 10 nm in diameter) were fabricated by an electrospinning method using a solution that contained PVP and manganese acetate and boric acid. Manganese oxyborate (Mn2OBO3) nanofibers were prepared by sintering the above composite fibers in air at 600, 700, and 800 degrees C, and the calcined nanofibers were characterized by X-ray diffraction (XRD), Raman, scanning electron microscopy (SEM), and transmission electron microscopy (TEM), respectively. After sintering at 600 degrees C, monoclinic phase Mn2OBO3 nanofibers of 180 +/- 20 nm in diameter were successfully obtained. Morphology analysis showed that the surface of the 700 degrees C-sintered Mn2OBO3 nanofibers (average size of 250 +/- 20 nm in diameter) was rough and they had fiberlike structure with packed particles. The 800 degrees C-sintered Mn2OBO3 fibers have necklace-like morphology. The crystallite size of the nanoparticles contained in nanofibers increases from 100 to 200 nm with increasing calcination temperature between 700 and 800 degrees C. The morphology changes of the Mn2OBO3 nanofibers can be attributed to the grain growth during the calcinations process. The Raman spectrum of Mn2OBO3 was provided and assigned. (C) 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim