Graphene-like g-C 3 N 4 nanosheet (GCN)/Fe 3 O 4 quantum dot (QD) nanocomposites were successfully synthesized by a facile electrostatic self-assembly method. Characterization shows that the GCN is at least several micrometers in size. The GCN/Fe 3 O 4 nanocomposites were used as photocatalysts for degradation of Rhodamine B (RhB) under visible light irradiation. After irradiation for 1.5 h, the degradation efficiency was 72.5% for pure g-C 3 N 4 , 81% for GCN-1 wt% Fe 3 O 4 , 95% for GCN-2 wt% Fe 3 O 4 , 60.46% for GCN-3 wt% Fe 3 O 4 and 57.2% for GCN-4 wt% Fe 3 O 4 , indicating that GCN-2 wt% Fe 3 O 4 nanocomposites had the highest photocatalytic activity. We deduce that the efficient separation of the photogenerated electron-hole pairs and the high specific surface area of GCN play important roles in the photocatalytic activity of the nanocomposites. In addition, the nanocomposites can be loaded with a model drug (Rhodamine B) and the loading capacity was as high as 108.6 mg g À1 , making it a potential candidate for photocatalysis and controlled magnetically targeted drug delivery.

Anatase TiO 2 -modified flower-like Bi 2 WO 6 nanostructures were prepared by a simple hydrothermal reaction followed by layer-by-layer deposition and calcination. The photocatalytic activity was evaluated using Brilliant Red X3B, an anionic azo dye, as the target organic pollutant under UV-Vis light irradiation. The experiment results showed that the photocatalytic activity of the hybrid increases first and then decreases with increasing loading amount of TiO 2 . The hybrid coated with four layers of TiO 2 (containing 20 wt-% TiO 2 ) showed the highest photocatalytic activity, which is 10.45 and 3.20 times higher than that of pure Bi 2 WO 6 and TiO 2 , respectively. The improved photocatalytic performance of TiO 2 -modified Bi 2 WO 6 nanostructures could be ascribed to the improved lightharvesting ability, efficient photo-generated electron-hole separation, and enhanced adsorption of the dye. This work may shed light on the design of complex architectures and the exploitation of their potential applications.