▎ 摘　　要

We developed a ternary nanocomposite of grapheneTiO2Fe3O4 (GTF) as a low-cost, recollectable, and stable photocatalyst for the degradation of organic dyes. The nanocomposite has been successfully prepared by successively growing TiO2 and Fe3O4 nanoparticles on the reduced graphene oxide (RGO). The as-synthesized GTF nanocomposite shows higher photocatalytic activity as compared with that of pure TiO2 nanoparticles and can be easily collected from water using a magnet. More importantly, benefiting from the presence of RGO, GTF can suppress the photodissolution behavior of Fe3O4 nanoparticles that usually occurrs in TiO2Fe3O4 binary nanocomposites, rendering it a highly stable photocatalyst. Furthermore, the GTF nanocomposite works well in different pH environments and is capable of eliminating mixtures of various dyes. In addition, the GTF is also able to degrade the dyes under sunlight. These attractive features make the GTF nanocomposite a promising photocatalyst for practical use in wastewater treatment.