Dendritic alpha-Fe2O3 hierarchical architectures for visible light driven photocatalysts

Large scale dendritic alpha-Fe2O3 hierarchical structures are successfully obtained through a facile hydrothermal approach. The morphology and microstructure of the as-synthesized products are characterized using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The individual alpha-Fe2O3 dendrite consists of a long central trunk with secondary and tertiary branches, which preferentially grow in a parallel direction with a definite angle to the trunk. A possible formation mechanism for the as-prepared product is proposed. Photocatalytic experimental results indicate that Congo red (CR) can be degraded nearly completely (over 95%) after 45 min under visible light irradiation. Also, degradation efficiencies of the alpha-Fe2O3 products with different morphologies toward CR were investigated, revealing that the dendritic structures possess superior photocatalytic activity. The as-synthesized dendritic alpha-Fe2O3 products may have potential application in wastewater treatment.