Abstract
BACKGROUND: Nanoparticulate titanium dioxide (TiO~2~) has the advantages of high chemical stability, high photocatalytic activity to oxidise pollutants in air and water, relatively low price and non‐toxicity. However, its high surface energy leads to the aggregation of nanoparticles. In addition, the wide band gap of TiO~2~ (3.2 eV) only allows it to absorb ultraviolet (UV) light (<387 nm), which represents just a small fraction (3–5%) of the solar photons. These factors have limited its use in many fields. In this study, nanoparticulate TiO~2~ was modified by polyaniline (PANI) in order to enhance its photoactivity under UV light and sunlight illumination.
RESULTS: TiO~2~ nanoparticles were modified by PANI via a chemical oxidative method. The introduction of small amounts of PANI enhanced the dispersion of TiO~2~ nanoparticles and improved the photocatalytic activity under UV light. In addition, the band gap energies of all PANI/TiO~2~ nanocomposites were lower than that of neat TiO~2~ nanoparticles, so the PANI/TiO~2~ nanocomposites can be excited to produce more electron–hole pairs under sunlight, which could result in higher photocatalytic activities.
CONCLUSION: The modification of nanoparticulate TiO~2~ by PANI can increase its photoactivity in the process of phenol degradation under UV light and sunlight illumination. Copyright © 2008 Society of Chemical Industry