Electron scavenger of thin layer Carbon coated and Nitrogen doped P25 with enhanced photocatalytic activity under visible light fluorescent lamp

Abstract

The commercially available and relatively cheap Degussa P25, TiO2 (80% anatase and 20% rutile) was modified to produce Carbon coated and Nitrogen doped P25. The modified photocatalyst was produced by using peat as the carbon precursor. The results showed that a thin layer of carbon in graphite form was deposited on the surface of P25 by which N atoms were also incorporated into the lattice of TiO2 by substituting the sites of oxygen atoms. From PL analysis, it was shown that the Carbon coated and Nitrogen doped P25 improved photocatalytic activity by acting as electron scavengers as well as reduced the electron–hole pair recombination. The photocatalytic activity of Carbon coated and Nitrogen doped P25 was examined by degradation of anionic Cibacron Brilliant Red or otherwise known as reactive red 4 (RR4) dye under visible light fluorescent lamp irradiations. The results indicated that the Carbon coated and Nitrogen doped P25 had enhanced photocatalytic activity and excellent photocatalytic stability even up to the 5th cycle of reuse. Its photocatalytic activity was almost 2 times faster than pristine P25. Carbon coated and Nitrogen doped P25 was not visibly active under low intensity visible light source (45-W) but showed clear photoactivity under a higher intensity visible light source (125-W).