OICC Press Journal of Nanostructure in Chemistry 2193-8865 3 1 (December 2013) 2013 08 05 Synthesis, characterization, and investigation of optical and magnetic properties of cobalt oxide (Co3O4) nanoparticles 10.1186/2193-8865-3-69 EN Saeed Farhadi Department of Chemistry, Lorestan University, Khoramabad, 68135-465, IR Jalil Safabakhsh Department of Chemistry, Lorestan University, Khoramabad, 68135-465, IR Parisa Zaringhadam Department of Chemistry, Lorestan University, Khoramabad, 68135-465, IR Journal Article 2013 08 05 Abstract Spinel-type cobalt oxide (Co 3 O 4 ) nanoparticles have been easily prepared through a simple thermal decomposition route at low temperature (175°C) using carbonatotetra(ammine)cobalt(III) nitrate complex, [Co(NH 3 ) 4 CO 3 ]NO 3 ·H 2 O, as a new precursor. The structure and morphology of as-prepared Co 3 O 4 nanoparticles were characterized by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), UV–vis spectroscopy, Brunauer-Emmett-Teller specific surface area measurement and magnetic measurements, and thermogravimetry/differential thermal analysis. The FT-IR, XRD, and EDS results indicated that the product was highly pure well-crystallized cubic phase of Co 3 O 4 . The TEM images showed that the product powder consisted of dispersive quasi-spherical particles with a narrow size distribution ranged from 6 to 16 nm and an average size around 11 nm. The magnetic measurements confirmed that the Co 3 O 4 nanoparticles show a little ferromagnetic behavior which could be attributed to the uncompensated surface spins and/or finite size effects. The ferromagnetic order of the Co 3 O 4 nanoparticles is raised with increasing the decomposition temperature. Using the present method, Co 3 O 4 nanoparticles can be produced without the need of expensive organic solvents and complicated equipments.