PHOTOELECTROCATALYTIC DEGRADATION OF METHLENE BLUE USING PT-CNT/TIO2 COMPOSITES UNDER VISIBLE LIGHT

摘要

Although titanium dioxide (TiO2) has been extensively investigated as a photocatalyst for the environmental purification of contaminated water and air, it is active only under illumination with UV light at wavelengths below 400nm because of the large band gap (3.2 eV) for anatase TiO2. Unfortunately, only ca. 4% of the solar radiation that reaches the Earth's surface exists in the UV region; indeed, more than 45% lies in the visible region. To develop a practical TiO2-based photocatalytic process, majority of studies on TiO2 focused on either enhancing its photocatalytic activity or extending its absorption spectrum from UV to the visible range by adding a second elements or support materials to the TiO2 bulk structure.