PHOTOCATALYTIC PROPERTIES OF TiO2/CNTs FILMS WITH DIFFERENT MORPHOLOGY ON STAINLESS STEEL SUBSTRATES

CNTs-TiO2 films with different morphology were fabricated on stainless steel substrates through chemical vapor hydrolysis deposition (CVHD) process and sol-gel process, respectively. Their morphology was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The photocatalytic properties of the films were tested in the degradation of methyl orange by UV light irradiation. The results revealed that TiO2 nanoparticles could form a continuous layer on the surface of CNTs through CVHD process. While for sol-gel process, most TiO2 nanoparticles were isolated and only a small amount of TiO2 nanoparticles attached on the surface of CNTs. And the photocatalytic property of TiO2/CNTs film synthesized through CVHD process was better than that of TiO2/CNTs films synthesized through sol-gel process. Electrochemical impedance spectroscopy (EIS) analysis illuminated that TiO2/CNTs synthesized through CVHD process displayed a smaller resistance than the sample which was synthesized through sol-gel process and certified that the close combination between TiO2 and CNTs could minimize recombination of photogenerated electrons and holes, and thus promote the photocatalytic property.