[Bmim][TfO] ionic liquid-assisted oriented growth of Co3O4 nanoworms

Monodispersed worm-like structure of Co3O4 nanocrystals of 20 nm width and 100-200 nm length are prepared directly without any intermediate product by 1-n-butyl-3-methylimidazolium trifluoromethane sulfonate ionic liquid ([Bmim][TfO] IL) assisted precipitation method. The higher concentration of [Bmim][TfO] IL in the reaction medium leads to the formation of homogeneous nanoworms. The effect of synthesis temperature and the oxidizing agent (H2O2) on the Co3O4 particle's morphology and their magnetic properties are discussed. Thermogravimetric analysis (TGA), powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) analysis were used to characterize the Co3O4 monodispersed nanoworms. The magnetic property of the spinel Co3O4 nanoworms is highly dependent on crystalline domains and exhibits weak ferromagnetic behavior with a narrow hysteresis loop opening. (C) 2012 Elsevier Ltd. All rights reserved.