Preparation And Physical And Chemical Properties Of Nano Tio <sub> 2 </ Sub> And Its Hybrid Films

Environmental pollution has received special attention. Photo degradation of organic contaminant perhaps is the most prospective environmental purification technology due to its low cost, without secondary pollution and ease of processing. Among various oxide semiconductor photo-catalysts, titania has received widespread attention in the fields of photo decomposition and environmental protection due to its long-term stability, cost effectiveness and nontoxic properties. In this paper, the nano-sized TiO2 powders and films were prepared by sol-gel method and the films were dye sensitized by octa-alkoxy naphthalocyanine. The characterizations of the films have been completed by XRD, FT-IR and AFM techniques. Photo-catalytic degradation of salicylic acid over the TiO2 powder and films was investigated.The results show that the smaller the grain size is, the higher the photo-catalytic activity is. Better photo-catalytic activity was obtained when the salicylic acid was exposed under 310nm Ultraviolet-light. After radiated for 24h, the degradation ratio of salicylic acid reached to 95%. The photo-catalytic activity of porous film is obviously larger than the compact film. The photo-catalytic activity of porous films increased when the coating cycles increased. The highest photo-catalytic activity was obtained when the film was coated for 10 times. The presence of zinc-ion in TiO2 films was found to increase the photo-catalytic activity of TiO2 films in degradation of salicylic acid. The best catalytic activity was observed in TiO2 film with 0.5% Zn2+. After radiated for 24h, the degradation ratio of salicylic acid was about 41%.Octapentyloxy-2, 3-naphthalocyanine and octaoctyloxy-2, 3-naphthalocy-anine were synthesized by using molecular fragments method. The naphthalocyanine LB films and TiO2/naphthalocyanine alternating film were successfully prepared by using Langmuir-Blodgett (LB) technique. The results of photo degradation of salicylic acid show that both the TiO2/ naphthalocyanine alternating film and the naphthalocyanine adsorbed TiO2 films have enhanced the photo-catalytic behavior of the TiO2 film, and the alternating film has better photo-catalytic activity. After radiated for 24h, the degradation ratio of salicylic acid was about 42%.