Morphological, Structural and Optical Properties of Ba-Doped NiO Nanostructure Thin Films

Authors M.Z. Merad1, L. Fellah2, A. Diha3

1Exploitation et Valorisation des Ressources Naturelles en Zones Arides, 30000 Ouargla, Algeria

2Faculty of Hydrocarbons and Renewable Energies and Earth and Universe Sciences, University of Kasdi Merbah, 30000 Ouargla, Algeria

3Department of Mechanical Engineering, University Larbi Tébessi, Tébessa 12000, Algeria

Issue Volume 15, Year 2023, Number 5
Dates Received 21 August 2023; revised manuscript received 14 October 2023; published online 30 October 2023
Citation M.Z. Merad, L. Fellah, A. Diha, J. Nano- Electron. Phys. 15 No 5, 05013 (2023)
PACS Number(s) 61.43.Dq, 68.55. Ln,68.55.jd
Keywords Spray pyrolysis (9) , Ba doped NiO, Thin films (60) , Band gap (29) , Urbach energy (3) , Grain size (4) .

This paper reports the effect of barium doping on NiO thin films. Undoped and doped films thin films were deposited on a glass substrate at 450 °C using pneumatic spray pyrolysis technique (PSPT) with different concentrations of barium (0 – 8 at. %). X-ray diffraction patterns show the polycrystalline nature of the films with the preferred orientation (111). No other barium metal cluster and impurity phases have been observed with Ba doping. The crystal size of the deposited thin films was calculated using the Debye-Scherrer formula for the two orientations (111) and (200), and from the SEM photographs, we found values ranging from 11.95 to 39.06 nm in both cases. In the visible region, the optical transmission of Ba-doped NiO thin films dropped by up to 46 % when compared to undoped NiO thin films (79 %). The band gap was found to be decreasing in the range of 3.742 – 3.503 eV with Ba doping. The Urbach disorder energy clearly increases from 262.9 to 356.64 meV when passing from the undoped thin layer to the thin layer doped at 2 at. %, then decreases to the minimum 303.14 meV for a barium doping of 8 at. %, allowing the atoms to find a good site, i.e. thin films become homogeneous and highly crystallized. The roughness was calculated using SEM image analysis. Its values were ranged between 23.26 – 39.06 nm.

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