Comparative Study of Anodized TNTs and S-TNTs on Ti Plates for Effective Methylene Blue Degradation under UV LED and Direct Sunlight

Abstract

The key findings of this research are focused on enhancing the degradation of methylene blue dye with titania nanotubes acting as catalysts under benign UV LED and sunlight. By comparing pristine and sulfur-doped titania, the study reveals that the doped-titania with anatase phase demonstrates a superior photocatalytic activity than pristine titania with mixed phases, achieving a remarkable 98% degradation of dye within 120 minutes under direct sunlight with a small amount of hydrogen peroxide. This enhanced performance is attributed to the 10.7 μm longer and well-arranged nanotubes, effective surface area, better bandgap of 2.39 eV, effective anatase phases, and a lower 20 nm crystallite size. The study underscores the importance of anodization and sulfur doping using titanium plates to tailor the properties of the resultant nanotubes. Also, it indicates a cost-effective dye removal method without secondary pollution, offering a practical and optimistic solution to environmental challenges. The effective titania nanotubes for photocatalytic application in environmental remediation were identified through field emission scanning electron microscope, energy dispersive X-ray analysis, X-ray diffraction analysis, and diffuse reflectance analysis, providing valuable insights and inspiring future research and application in this field.