| 초록 |
Glucose adsorbed-TiO2 nanoparticles show photoactivity under visible light (λ＞420 nm) through the ligand-to-metal charge transfer (LMCT) mechanism. Although glucose has been often utilized as a hole scavenger in TiO2-based photocatalytic systems, the fact that TiO2-glucose can form a LMCT complex that absorbs visible light has not been recognized. The TiO2-glucose LMCT complex induced a marked red-shift in the absorption spectrum which extended to 600 nm, and the visible light absorption gradually decreased with decreasing the concentration of glucose. The TiO2-glucose complex exhibited remarkable visible light activities for the reduction of Cr(VI) to Cr(III) and the reduction of O2 to H2O2. The observed visible light activities were significantly inhibited when the TiO2 surface was fluorinated, because the surface fluorides inhibited the formation of LMCT complex of glucose. |
