rteü-femüd Recep Tayyip Erdogan University Journal of Science and Engineering 2687-2315 2757-7686 Recep Tayyip Erdoğan Üniversitesi 10.53501/rteufemud.1395013 Material Physics Condensed Matter Physics (Other) Malzeme Fiziği Yoğun Madde Fiziği (Diğer) Influence of Thermal Annealing on the Band-Gap of TiO2 Thin Films Produced by the Sol-Gel Method Influence of Thermal Annealing on the Band-Gap of TiO2 Thin Films Produced by the Sol-Gel Method https://orcid.org/0000-0003-1887-848X Tomakin Murat RECEP TAYYIP ERDOGAN UNIVERSITY https://orcid.org/0000-0001-8827-1590 Kanmaz İmran RECEP TAYYIP ERDOGAN UNIVERSITY https://orcid.org/0000-0002-7006-5841 Aytemiz Göksel RECEP TAYYIP ERDOGAN UNIVERSITY https://orcid.org/0000-0001-5791-8937 Manır Melih RECEP TAYYIP ERDOGAN UNIVERSITY https://orcid.org/0000-0002-8758-4760 Nevruzoğlu Vagif RECEP TAYYIP ERDOGAN UNIVERSITY 06 30 2024 5 1 49 56 11 23 2023 03 06 2024 Copyright © 2020, Recep Tayyip Erdoğan Üniversitesi Fen ve Mühendislik Bilimleri Dergisi 2020 Recep Tayyip Erdoğan Üniversitesi Fen ve Mühendislik Bilimleri Dergisi

In our study, we employed the spin coating method to produce TiO2 thin films on quartz glass using a solution with a concentration of 0.5M. After the coating process, the samples underwent heat treatment at 100°C in air ambient for drying. Subsequently, annealing was carried out at four different temperatures, namely 300°C, 500°C, 700°C, and 900°C, for a duration of 60 minutes. The produced samples underwent comprehensive analyses, including Scanning Electron Microscopy (SEM), Energy Dispersion Spectroscopy (EDS), X-ray Diffraction (XRD), and optical measurements, to investigate their structural and optical properties. Optical measurements revealed that the highest average transmittance values were obtained for samples annealed at 300°C and 500°C, with percentages of 82.33% and 80.25%, respectively. Remarkably, the maximum transmittance of 99.58% was recorded for films annealed at 500°C. Additionally, band-gap calculations were performed using the Tauc method based on optical measurements of samples exposed to different annealing temperatures. According to our findings, samples annealed at 300°C, 500°C, 700°C, and 900°C exhibited band-gap values of 3.42eV, 3.40eV, 3.38eV, and 3.29eV, respectively.

In our study, we used the spin coating method to produce TiO2 thin films on quartz glass using a solution with a concentration of 0.5M. After the coating process, the samples were dried in air at 100°C. Subsequently, annealing was carried out at four different temperatures, namely 300°C, 500°C, 700°C, and 900°C, for a duration of 60 minutes. Comprehensive analyzes including Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), X-ray Diffraction (XRD) and optical measurements were carried out to investigate the structural and optical properties of the samples. Optical measurements showed that the highest average transmittance values were obtained for samples annealed at 300°C and 500°C, with percentages of 82.33% and 80.25%, respectively. Remarkably, the maximum transmittance of 99.58% was recorded for films annealed at 500°C. Additionally, band-gap calculations were performed using the Tauc method based on optical measurements of samples exposed to different annealing temperatures. According to our results, samples annealed at 300°C, 500°C, 700°C, and 900°C exhibited band-gap values of 3.42eV, 3.40eV, 3.38eV, and 3.29eV, respectively.

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