Enhanced optical, structural and antibacterial properties of ZnO doped TiO2 composites

Mehmet Eymen Sumer; Bengu Ozugur Uysal

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arXiv · 2312.09338

Enhanced optical, structural and antibacterial properties of ZnO doped TiO2 composites

Mehmet Eymen Sumer·Bengu Ozugur Uysal

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Abstract

Bacterial infections are a common problem in daily life that can affect human health. Researchers are looking for valuable materials that can help prevent such infections and environmental pollutants. Thin films are a well-known application for photocatalytic and biological activity. Therefore, thin-film formation is an excellent way to address these problems, thanks to its nanosized thickness and enhanced monolayer or multilayered structure. Titanium oxide (TiO2) is the most common material used to produce thin films due to its various traits that enhance the activity of thin films, such as structural and optical properties. However, the single usage of pure TiO2 has certain limitations over these problems. Therefore, new techniques, called doping, need to be implemented to overcome these limitations. Doping is a standard method for manipulating material properties to provide enhanced functionality. ZnO was selected as a dopant because of its good bandgap energy and high electron activity. Thus, this research mainly focused on the differences in antibacterial, structural, and optical activity between pure TiO2 and ZnO-doped TiO2. The sol-gel method was used in this research for several different thin-film deposition methods due to its easy progression at room temperature, low cost, and homogeneity traits. The antibacterial activity of pure and doped TiO2 thin films was analyzed using the standard ISO 22196 protocol against gram-positive Staphylococcus aureus and gram-negative Escherichia coli. As a result, XRD and UV-vis spectrophotometer measurements show that our dopant ZnO efficiently enhances the bandgap energy of pure TiO2. The correlation between dispersibility and homogeneity was achieved in the concentration range ZTA-B-R (5-10).

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Mehmet Eymen Sumer, Bengu Ozugur Uysal. 2023-12-14. Enhanced optical, structural and antibacterial properties of ZnO doped TiO2 composites. https://arxiv.org/abs/2312.09338

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