The Tio <sub> 2 </ Sub>-cnts Composite Nano-materials To Build Its Optical And Electrical Properties

In this paper, TiO2-CNTs nanocomposites had been successfully fabricated by water-organic two-phase separated hydrolysis-solvothermal (HST) processes in the toluene under solvothermal condition, and characterized by XRD, SEM, TEM, XPS, SPS. Nanocomposites film electrodes were prepared using doctor-blade technique and the photoelectrochemical characteristics of the film electrodes were studied, especially the impact of different content CNTs on photocatalytic and photoelectrochemical characteristic. The formation mechanisms of composite structures were discussed.Composite samples of uniform morphology were synthesized by controlling temperature of acidification of the CNTs and a stable dispersion system was formed by pre-mixing CNTs, butyl phthalate and toluene. The results showed that nano-composite structure could be formed under proper acidification temperature, and a better dispersion system of organic phase what needed to be obtained after pre-mixing treatment. The structure of the CNTs was seriously damaged under a higher acidification temperature, while it did not play the role of surface polarity when the temperature was low. The CNTs which were treated by acidification under suitable temperature was mixed with butyl titanate, and then the butyl titanate was covered on the surface of the CNTs which was propitious to form good organic phase dispersion system. Then the CNTs were composited with butyl titanate directly under hydrothermal process, which was the key point to form good composite structures. The samples were not heated at high temperature on next steps, so that the composite structures were not destroyed because of expansion.The sample with appropriate CNTs content had better photocatalytic performance, even than the P25-TiO2. The role of CNTs in improving photocatalytic performance was measured by SPS. It could be found that photocurrent of the TiO2 was improved by tests of IV and IT under the existence of CNTs, which was consistent with the result of the photocatalytic efficiency. In addition, the nano-TiO2-AC composites were obtained with the same approach using activated carbon instead of carbon CNTs, and the photocatalytic activity had also been enhanced.