Band gap energy and photocatalytic efficiency of TiO₂ thin films deposited via dip and spin coating under visible light

Mohd Rosli, Zulkifli and Johari, Nur Dalilah (2025) Band gap energy and photocatalytic efficiency of TiO₂ thin films deposited via dip and spin coating under visible light. Journal of Power and Energy Engineering, 13 (12). pp. 1-13. ISSN 2327-5901

Text 00585030220261035442998.pdf Available under License Creative Commons Attribution. Download (1MB)

Abstract

TiO2 thin films were prepared via a water-based sol-gel method and deposited using dip and spin coating techniques to investigate the relationship between band gap energy and photocatalytic efficiency under visible light irradiation. The influence of deposition method and annealing temperature on the structural phase, optical properties, and methylene blue (MB) degradation performance was examined. Dip-coated films exhibited a transition from anatase to a mixed anatase-rutile phase above 300˚C, while spin-coated films predominantly formed the brookite phase. The band gap of dip-coated films decreased from 2.81 eV at 200˚C to 2.48 eV at 500˚C, whereas spin-coated films showed a minimum of 2.45 eV at 300˚C, achieving the highest MB degradation efficiency of 97.7%. Higher temperatures led to band gap widening and reduced photocatalytic activity. These findings demonstrate that spin-coated TiO2 thin films annealed at 300˚C exhibit optimal structural and optical properties for visible-light-driven photocatalysis.

Item Type:	Article
Uncontrolled Keywords:	TiO2 Thin Films, Photocatalysis, Spin Coating, Methylene Blue, Sol-Gel, Dip Coating
Divisions:	Faculty Of Industrial And Manufacturing Technology And Engineering
Depositing User:	Norfaradilla Idayu Ab. Ghafar
Date Deposited:	15 Jul 2026 00:46
Last Modified:	15 Jul 2026 00:46
URI:	http://eprints.utem.edu.my/id/eprint/29943
Statistic Details:	View Download Statistic

Actions (login required)

View Item