TiO2 for efficient photocatalytic decomposition of acetaldehyde: An investigation of the effects of annealing temperature, humidity, and binder

Abstract

TiO₂ photocatalysts were synthesized by simple sol gel method and annealed at 300, 500, and 600°C. Photocatalytic performance of as-prepared TiO₂ and annealed TiO₂ samples was evaluated for the decomposition of acetaldehyde under UV light irradiation. TiO₂ annealed at 500°C (T500) showed the highest acetaldehyde removal performance, which was attributed to combined effects of its crystallinity, defect density, surface area, narrow band gap with the dual phase of TiO₂, and lifetimes of charge carriers. In humid conditions, overall acetaldehyde removal performance of T500 slightly decreased, but the extent of total oxidation of acetaldehyde into CO₂ increased in high humidity as compared to dry conditions. Moreover, fixation of T500 on mica sheet using binders resulted in promising photocatalytic performance, making it a potential candidate for air purification applications. Fourier-transform infra-red (FT-IR) analysis confirmed the stable existence of binder structure under dry air and UV treatment, which is crucial for real applications.