Fe@Fe_2O_3/g-C_3N_4复合光催化剂的制备及其性能

Preparation and Catalytic Property of Fe@Fe_2O_3/g-C_3N_4 Composite Photocatalyst

通过高温煅烧三聚氰胺制备了石墨相氮化碳g-C_3N_4,再以硼氢化钠(NaBH_4)为还原剂,室温下还原氯化高铁(FeCl_3·6H_2O)制备出了具有核壳结构的Fe@Fe_2O_3纳米线。然后分别通过超声法和溶剂热法制备了Fe@Fe_2O_3/g-C_3N_4复合光催化剂,并利用X-射线衍射(XRD)、扫描电镜(SEM)、透射电镜(TEM)等表征方法对其进行表征。所得样品的光催化性能通过在可见光下(λ≥400 nm)光催化降解罗丹明B(RhB)溶液来评估。研究表明,超声法制备的Fe@Fe_2O_3/g-C_3N_4复合催化剂具有优良的可见光催化性能,其催化活性明显高于单组分的催化活性,一般认为Fe@Fe_2O_3与g-C_3N_4之间有一定的协同作用,从而可以提高材料的催化活性。同时,研究发现该催化体系中起关键作用的主要活性物种是超氧自由基。

Graphitic carbon nitride g-C3N4 was prepared by calcination of melamine at high temperature.Core-shell Fe @ Fe2O3 nanowires were obtained by reduction of ferric chloride（FeCl3·6 H2O） with sodium borohydride（Na BH4） as reducing agent at room temperature. Fe@ Fe2O3/g-C3N4 composite were synthesized by ultrasonic method and solvothermal method. The obtained composite was characterized by X-ray diffraction,scanning electron microscopy and Transmission electron microscope. The photocatalytic activity of Fe @ Fe2O3/g-C3N4 composite was evaluated by the degradation of Rh B under visible light irradiation（λ≥400 nm）. The results shows that Fe@ Fe2O3/g-C3N4 composite prepared by ultrasonic method exhibited excellent photocatalytic activity. The catalytic activity of Fe@ Fe2O3/g-C3N4 composite was obviously higher than that of single component catalyst. We believe that there is a synergistic effect between Fe @ Fe2O3 and g-C3N4,which can improve the catalytic activity of Fe @ Fe2O3/g-C3N4 composite. Also it was discovered that the main active specie is superoxide radical,which is responsiblefor Rh B degradation.