The physical properties of spinel cubic Co3O4 thin films prepared by a PSM

Abstract

Undoped and Mn-doped Co3O4 films were deposited on heated glasses substrates (TS = 400°C) using a homemade pneumatic spray method (PSM). The solution concentration and deposition time are 0.1 M and 4 min respectively. The effect of manganese doping concentration on structural, optical and electrical properties of cobalt oxide were investigated. The elaborated films were characterized by X-ray diffraction, UV-Vis spectroscopy, atomic force microscopy (AFM) the three-dimensional (3D), energy dispersive spectroscopy (EDS), and four points probe measurements. The XRD study showed that all films were polycrystalline consisting with spinel cubic phase orientated along to (111) plane. The lattice strain and crystallite size were estimated by Williamson-Hall method. The morphology of Mn-doped Co3O4 thin films shows a homogeneous surface with straight acicular nanorods (SANRs). EDS analysis showed the presence of peaks associated with Co, O and Mn elements which confirm the composition of the thin films. The optical band gaps varies from 1.42±0.07 to 1.47±0.07 eV of Egop1and Egop2 varies from 1.87±0.10 to 2.11±0.11 eV. In addition, the electrical measurement show a maximum electrical conductivity (σ= 15.54±0.78 (Ω.cm)-1) at 6% wt of Mn.