Synthesis And Performance Of Titanium Dioxide And Its Graphene Composites

Light catalysis has been of great interest due to the potential applications in new energy source, waste waer and air purification. Ti O2 is cheap, non-toxic and good chemical stability, which are widely accepted as photocatalyst for degradation of organic pollutants in waste water, air purification, photo-splitting water hydrogen production. However, due to large the forbidden band width of titanium dioxide(anatase phase of forbidden band width is 3.2 e V, and rutile phase of the forbidden band width is 3.0 e V), it can only absorb ultraviolet light with wavelength less than 380 nm, which greatly limites its photocatalytic performance. Moreover, the excit electronics and hole generated by ultraviolet conbine quickly inside, and can’t effective migrate to the surface of the catalyst, which greatly restrict its photocatalytic activity. Therefore, synthesis of materials with a narrow forbidden band width and effective inhibition of photoproduction is still a challenging Various methods were used to adjust the such as mixed with precious metals in the Ti O2 morphology such as mixing precious metals, metal oxide, carbon nanomaterials Ti O2 particals, exposed the highly acive crystal facet. In this paper, the photocatalytic activity of Ti O2 was imptoved through effective control of Ti O2 morphology to exposes its high-energy surfaces and use graphene as high efficiercy conductive media. The results are listed as follows:(1) The morphology of Ti O2 was carefully studied by regulating the reaction time, concentration of reactants, reaction temperature, the reaction kettle body pressure. Further optimization of experimental parameters were collected to high quality Ti O2 particles.(2) Titanium dioxides with different proportion of {001} and {100} crystal face were synthetized by using the hydrothermal method with assistance of hydrochloric acid and hydrofluoric acid. The influence of crystal faces of {001} and {100} on the photocatalytic activity of Ti O2 was studied to further determine the active order of {001} and {100} crystal faces.(3) Titanium dioxide and graphene composite material was synthetized by using one step hydrothermal method and two step hydrothermal synthesized to increase the rate of electron transfer through graphene conductive network. Great improvement of the photocatalytic performance was found in the composite structure.