In_2O_3与CuO掺杂TiO_2纳米纤维光催化脱汞的研究

Photocatalytic Removal of Mercury Using In_2O_3 or CuO Doped TiO_2 Nanofibers

采用静电纺丝法制备In_2O_3和CuO掺杂TiO_2的纳米纤维,使用纤维进行模拟燃煤烟气光催化脱汞的研究.利用X射线衍射(XRD)、扫描电子显微镜(SEM)和透射电子显微镜(TEM)等手段对纤维的晶体结构和形貌进行了表征.实验考察了TiO_2、TiO_2-In_2O_3和TiO_2-CuO分别在无光、可见光和紫外光下的脱汞效率,以及In_2O_3和CuO的最佳掺杂量,并分析了纤维光催化脱汞的机理.结果表明当In_2O_3的质量含量为10%时,TiO_2-In_2O_3在紫外光下的脱汞率有了很大提高,可达到93%,其原因是In_xTi_1-_xO_2/In_2O_3复合结构的形成.当CuO的质量含量为10%时,TiO_2-CuO在可见光下的脱汞效率有了较大提高,电子的跃迁是TiO_2-CuO在可见光下催化活性提高的主要原因.

Nanofibers of TiO2-In203 and TiO2-CuO prepared by the electrospinning method are proposed to use as catalysts for the removal of elemental mercury （Hg） from simulated flue gas. The nanofibers were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM） as well as transmission electron microscopy （TEM）. TiO2-In203 and TiO2-CuO nanofibers were used to remove Hg from simulated flue gas in the dark, under visible light and UV light respectively. The optimum doping contents of In203 and CuO were investigated. The photocatalytic mercury removal mechanism was also analyzed. The results showed that the Hg removal efficiency over TiO2-In203 could reach 93% under UV irradiation when the doping content of In203 was 10%. The increased photocatalytic efficiency was attributed to the information of InxTil-xO2/InO3. In addition, Doping 10% CuO into TiO2 enhanced Hg removal efficiency from 6% to 30% under visible light irradiation, which was probably due to the electron transition.