Structural Design Of TIO2/carbon Nanofiber Composites And Their Photocatalytic Degradation Properties

In recent years,carbon nanofibers have been widely used in the field of photocatalyst carriers due to their large specific surface area,high porosity and good conductivity.Therefore,assembling TiO₂ nanoparticles onto the surface of carbon nanofibers has become a trend in the field of photocatalysis.Among the various preparation methods,the blended spinning and post-assembly method are used widely.In this paper,we researched firstly the structure and property of TiO₂/carbon nanofiber composites prepared by hydrothermal reaction and blended spinning.Then,a new method for preparing TiO₂/carbon nanofiber composite with high TiO₂ loading and strong interfacial action was proposed,and the effect of unique structure on the performance for degradation of organic dyes?Rhodamine B?was investigated.The main contents of this article include two aspects:?1?The effects of carbonization temperature on the structure and photocatalytic degradation of TiO₂/carbon nanofibers composites prepared by hydrothermal reaction and blending spinning were summarized.The results showed that TiO₂/carbon nanofiber composites prepared by hydrothermal reaction had good photocatalytic activity,but the cycling stability was poor.However,the composites prepared by the blending spinning possessed excellent cycle stability,but the degradation rate was low.?2?It was proposed that the half-coated TiO₂/mesoporous carbon nanofiber composites were prepared by adding foaming agent?betaine?into the spinning solution and the effect of carbonization temperature on the photocatalytic degradation of the composites was studied.The results showed that with the increase of carbonization temperature,the the nanoparticles gradually occurred on the surface of carbon nanofibers to form a stable half-coated structure.The specific surface area of composites increased from 68.94 m2 g'1 to 390.56 m2 g-1 and the mesoporous structure gradually appeared on the carbon nanofibers.The photocatalytic degradation for rhodamine B increased first and then declined.When the carbonization temperature was 800 ?,the degradation rate is 98.2%.The results showed that the cyclic performance of the composites is good,and the degradation rate of the composites is 95.8%after 5 cycles.Having investigated the structure and property of half-coated TiO₂/mesoporous carbon nanofiber composites,we concluded that the disadvantages of composited prepared by hydrothermal reaction and blending spinning,respectively were overcame.And the high catalytic activity and stable cycling performance had achieved.