Structural and Optical Characteristics of Co3O4 Nanostructures Prepared by DC Reactive Magnetron Sputtering


Cobalt oxide thin films were prepared by dc reactive magnetron sputtering system using different gas mixing ratios of argon and oxygen. The influence of gas mixing ratio on the structure of cobalt oxide thin film was studied by x-ray diffraction (XRD) patterns, which confirm the crystalline nature of the prepared samples. A well-defined diffraction peak at about 37° (311) was observed, which indicates that the spinel structure (Co3O4) of cobalt oxide was obtained. The particle size of the prepared Co3O4 was determined by field-emission scanning electron microscopy (FE-SEM) and the elemental composition of this oxide was evaluated by energy-dispersive x-ray dispersive (EDX) spectroscopy. The energy band gap was determined in the range 2.01-2.06 eV. Due to the homogeneous optical and structural characteristics of the prepared cobalt oxide thin films, they can be used as ion-storage layer in electrochromic or photoelectrochromic device.