Document Type: Original Paper


1 Department of Chemical Engineering, College of Engineering, Shahrood Branch, Islamic Azad University, Shahrood, Islamic Republic of Iran

2 Department of Chemistry, Faculty of Science, Golestan University, Gorgan, Islamic Republic of Iran

3 Research institute of Petroleum Industry, the west entrance toAzadi stadium, Olympic Blv., Tehran, Islamic Republic of Iran

4 Department of Chemistry, The University of Burdwan, Burdwan, West Bangal, India


Cobalt oxide (Co3O4) nanoparticleshave been synthesized by hydrothermal method using mixture of cobalt(II)chloride, Triton X-100 and KOH in an autoclave at 180 °C for 6 h followed by heating at 400 ºC for 3 h in air. The product have been characterized by Fourier transform infrared (FT-IR), UV-Vis spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Optical properties of the Co3O4nanoparticleshave revealed the presence of two band gaps, viz.2.9 and 2.4 eV. Data fromvibrating sample magnetometer (VSM) confirm the purity of the product along with single phase paramagnetic behavior.