Preparation And Photocatalytic Hydrogen Production Performance Of Titanium Dioxide Nanocomposite

As a new type of material, nanomaterial is attractting much attentions because of its own unqiue structures and properties. It has been applied in microelectronics, optical, medical, textile, plastic, ceramic biological engineering and other fields. As a result, the preparation and exploring new application of nanomaterials is a hot topic of researchers. Titanium dioxide is a new type of semiconductor photocatalyst. There are many advantages, such as high effciency and low energy consumption, safety and moderate cost. It is expected to further improve the photocatalytic activity and quantum efficiency of titanium dioxide to fabricate heterojunction.Titanium dioxide nanomaterial was prepared by hydrothermal method in this paper. And C₃N₄ nanosheet and Au modified titanium dioxide nanomaterial composites were also sucessfully prepared. Scanning electron microscope, X-ray diffractometer, double-beam ultraviolet-visible spectrophotometer and specific surface area and pore size analyzer were used to investigate the morphology, phase structure and optical properties of titanium dioxide-based composites. The photocatalytic activities were investigated by hydrogen production with methanol as sacrificial agent, and the mechanism of hydrogen production was also investigated briefly. The results showed that the as-prepared titanium dioxide seemed like willow leaf or grapefruit granular with the size of 50⁴00nm. The as-prepared titanium dioxide was anatase with good dispersibility and good visible-light response. The photocatalytic activity of titanium dioxide was much higher than that of P25, and T125 had the highest photocatalytic activity. The particle size of C₃N₄/TiO₂ compositie is relatively bigger than T125 because of the effect of C₃N₄ sheet. And it is rutile titanium dioxide in C₃N₄/TiO₂ compositie. The absorption band edge had a redshift, and the visible light photocatalytic activity was improved. The catalyst with C/T=3:1 had the best photocatalytic activity and stability. The morphology and phase structure of dioxide nanomaterial loaded with Au particles did not changed yet with a widened visible light absorption band edge and improved photocatalytic activity in the same condition.