Structural, optical and electrical properties of electron beam evaporated TiOxNy films as selective solar absorber coatings

Berhane, D.; Rodrigues, M.O.; Henini, M.; Maaza, M.; Nuru, Z.Y.

Abstract

Titanium oxinitride (TiOxNy) solar absorber coatings were deposited at different oxygen partial pressures onto Cu, Si and glass substrates using electron beam evaporation technique. XRD diffraction patterns evidenced (111), (200) and (220) orientation of TiNx phase. The preferred orientation of the films changed with oxygen partial pressure. XPS revealed the intensity of both Ti 2P3/2 and Ti 2P1/2 increases as a function of oxygen flow, and also shifted towards higher binding energy, indicating more oxidized state of Ti species than that of TiO2 due to incorporation of nitrogen atoms. Formation of uniformly distributed spherical like particles and an increase in surface roughness of the TiOxNy films were observed as a function of oxygen partial pressure as depicted from SEM and AFM, respectively. Ellipsometric and resistivity measurements showed a shift from metallic to semiconductor behaviour of the TiOxNy films as oxygen flow changed. A solar absorptance value of 0.94 in the solar spectrum region and a low thermal emittance value of 0.05 were achieved for the TiOxNy solar absorber coatings prepared at the oxygen partial pressure of 7.5x10-5 Torr due to both interference and intrinsic absorption. This study confirmed that a single layer of TiOxNy film can be a good candidate as selective solar absorber.

Citation

Berhane, D., Rodrigues, M., Henini, M., Maaza, M., & Nuru, Z. (2020). Structural, optical and electrical properties of electron beam evaporated TiOxNy films as selective solar absorber coatings. Journal of Applied Material Science & Engineering Research, 4(1),

• Journal Article Type: Article
• Acceptance Date: Feb 6, 2020
• Online Publication Date: Feb 15, 2020
• Publication Date: Feb 15, 2020
• Deposit Date: Mar 3, 2020
• Publicly Available Date: Mar 4, 2020
• Journal: Journal of Applied Material Science & Engineering Research
• Electronic ISSN: 2689-1204
• Publisher: Opast Group
• Peer Reviewed: Peer Reviewed
• Volume: 4
• Issue: 1
• Article Number: 30
• Public URL: https://nottingham-repository.worktribe.com/output/4084409
• Publisher URL: https://opastonline.com/wp-content/uploads/2020/02/structural-optical-and-electrical-properties-of-electron-beam-evaporated-tioxny-films-as-selective-solar-absorber-coatings-jamser-20.pdf
• Related Public URLs: https://www.opastonline.com/journal-of-applied-material-science-engineering-research/