Effect of Spin-Coating Speed on the Structural, Morphological, Optical, and Photocatalytic Properties of ZnO Thin Films

Buse Selenay Başaran; Fethi Mehmet Akis; Erkan Fırıncı; Fatih Ersan

Effect of Spin-Coating Speed on the Structural, Morphological, Optical, and Photocatalytic Properties of ZnO Thin Films

Abstract

ZnO thin films were successfully deposited on glass substrates by the sol–gel spin-coating technique using different rotation speeds to investigate the influence of spin speed on their structural, morphological, optical, and photocatalytic properties. After each coating cycle, the deposited layers were preheated at 110 °C for 10 min, while the final multilayer films were annealed at 450 °C for 1 h. X-ray diffraction analysis revealed that all samples crystallized in the hexagonal wurtzite phase with a pronounced (002) preferred orientation, indicating c-axis-oriented growth. Among the investigated samples, the film prepared at 3000 rpm exhibited the highest crystallinity. Atomic force microscopy measurements showed that increasing spin speed reduced both grain size and surface roughness, leading to smoother and more uniform film surfaces. Optical characterization demonstrated high transparency in the visible region and a distinct absorption edge, with optical band gap values ranging from 3.17 to 3.18 eV. Photoluminescence spectra displayed strong near-band-edge emission accompanied by weak defect-related visible emissions. The gradual decrease in PL intensity with increasing spin speed suggests a lower concentration of defect states and reduced carrier recombination. Photocatalytic tests using methylene blue under UV illumination confirmed the effective photocatalytic activity of the ZnO films. These findings demonstrate that spin-coating speed is a critical processing parameter for tailoring the microstructure and functional properties of ZnO thin films for optoelectronic and photocatalytic applications.

Keywords

Supporting Institution

Scientific and Technological Research Council of Turkey (TUBITAK)

Project Number

125F056.

Ethical Statement

It is declared that during the preparation process of this study, scientific and ethical principles were followed and all the studies benefited from are stated in the bibliography.

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Details

Primary Language

English

Subjects

Material Physics, Surface Physics

Journal Section

Research Article

Authors

Buse Selenay Başaran
Türkiye

Fethi Mehmet Akis
Türkiye

Erkan Fırıncı
Türkiye

Fatih Ersan ^*
Türkiye

Publication Date

June 25, 2026

Submission Date

June 3, 2026

Acceptance Date

June 15, 2026

Published in Issue

Year 2026 Volume: 2 Number: 1

IZ

https://izlik.org/JA29ZC74AK

Cite

RIS / Bibtex

APA

Başaran, B. S., Akis, F. M., Fırıncı, E., & Ersan, F. (2026). Effect of Spin-Coating Speed on the Structural, Morphological, Optical, and Photocatalytic Properties of ZnO Thin Films. Smyrna Journal of Natural and Data Sciences, 2(1), 15-26. https://izlik.org/JA29ZC74AK

AMA

1.Başaran BS, Akis FM, Fırıncı E, Ersan F. Effect of Spin-Coating Speed on the Structural, Morphological, Optical, and Photocatalytic Properties of ZnO Thin Films. Smyrna Journal of Natural and Data Sciences. 2026;2(1):15-26. https://izlik.org/JA29ZC74AK

Chicago

Başaran, Buse Selenay, Fethi Mehmet Akis, Erkan Fırıncı, and Fatih Ersan. 2026. “Effect of Spin-Coating Speed on the Structural, Morphological, Optical, and Photocatalytic Properties of ZnO Thin Films”. Smyrna Journal of Natural and Data Sciences 2 (1): 15-26. https://izlik.org/JA29ZC74AK.

EndNote

Başaran BS, Akis FM, Fırıncı E, Ersan F (June 1, 2026) Effect of Spin-Coating Speed on the Structural, Morphological, Optical, and Photocatalytic Properties of ZnO Thin Films. Smyrna Journal of Natural and Data Sciences 2 1 15–26.

IEEE

[1]B. S. Başaran, F. M. Akis, E. Fırıncı, and F. Ersan, “Effect of Spin-Coating Speed on the Structural, Morphological, Optical, and Photocatalytic Properties of ZnO Thin Films”, Smyrna Journal of Natural and Data Sciences, vol. 2, no. 1, pp. 15–26, June 2026, [Online]. Available: https://izlik.org/JA29ZC74AK

ISNAD

Başaran, Buse Selenay - Akis, Fethi Mehmet - Fırıncı, Erkan - Ersan, Fatih. “Effect of Spin-Coating Speed on the Structural, Morphological, Optical, and Photocatalytic Properties of ZnO Thin Films”. Smyrna Journal of Natural and Data Sciences 2/1 (June 1, 2026): 15-26. https://izlik.org/JA29ZC74AK.

JAMA

1.Başaran BS, Akis FM, Fırıncı E, Ersan F. Effect of Spin-Coating Speed on the Structural, Morphological, Optical, and Photocatalytic Properties of ZnO Thin Films. Smyrna Journal of Natural and Data Sciences. 2026;2:15–26.

MLA

Başaran, Buse Selenay, et al. “Effect of Spin-Coating Speed on the Structural, Morphological, Optical, and Photocatalytic Properties of ZnO Thin Films”. Smyrna Journal of Natural and Data Sciences, vol. 2, no. 1, June 2026, pp. 15-26, https://izlik.org/JA29ZC74AK.

Vancouver

1.Buse Selenay Başaran, Fethi Mehmet Akis, Erkan Fırıncı, Fatih Ersan. Effect of Spin-Coating Speed on the Structural, Morphological, Optical, and Photocatalytic Properties of ZnO Thin Films. Smyrna Journal of Natural and Data Sciences [Internet]. 2026 Jun. 1;2(1):15-26. Available from: https://izlik.org/JA29ZC74AK