Lu doping nickel oxide thin films using sol-gel spin coated and density functional theory: optoelectronic and magnetic properties

Souraya Goumri-Said; Güven Turgut; Mohammed Benali Kanoun

doi:10.1016/j.heliyon.2023.e14874

Lu doping nickel oxide thin films using sol-gel spin coated and density functional theory: optoelectronic and magnetic properties

Heliyon. 2023 Mar 31;9(4):e14874. doi: 10.1016/j.heliyon.2023.e14874. eCollection 2023 Apr.

Authors

Souraya Goumri-Said¹, Güven Turgut^{2

3}, Mohammed Benali Kanoun⁴

Affiliations

¹ Physics Department, Colleges of Science and General Studies, P.O.BOX 50927, Alfaisal University, Riyadh, 11533, Saudi Arabia.
² Erzurum Technical University, Department of Basic Sciences Physics, 25240, Erzurum, Turkey.
³ Erzurum Technical University, 2D Material Research Group, YUTAM, 25240, Erzurum, Turkey.
⁴ Department of Mathematics and Sciences, College of Humanities and Sciences, Prince Sultan University, P.O. Box 66833, Riyadh 11586, Saudi Arabia.

Abstract

For the first time, sol-gel spin coating was used to fabricate thin films of NiO doped with lutetium. The films were characterized to determine their crystalline structure, surface morphology, and optical properties as a function of Lu doping concentration. The investigations revealed that the Lu-doped NiO films consisted of nano-polycrystalline particles with a cubic bunsenite structure and (200) preferential orientation. Optical studies indicated that the optical band gap of pure NiO widened with low levels of Lu incorporation before narrowing with higher concentrations. The Urbach energy value for pure NiO initially decreased with 1 at. % Lu-content, from 224 meV to 190 meV, and then continuously increased to 380 meV with more Lu-level. To investigate the effects of Lu doping on the electronics, magnetic, and optical properties of NiO, first-principle computations were performed. The results showed that bulk magnetization underwent significant modifications due to a high hybridization between the Lu-f/d and Ni-d states. This study suggests that NiO doped with lutetium could be used for spin-polarized transport devices and other spin-dependent applications.

Keywords: DFT+U; Electronic structure; Lu-doping; NiO; Spin coating.