Hierarchical FeWO4 Microcrystals: Solvothermal Synthesis and Their Photocatalytic and Magnetic Properties

Highly hierarchical platelike FeWO4 microcrystals have been synthesized by a simple solvothermal route using FeCl3·6H2O and Na2WO4·2H2O as precursors, where ethylene glycol (EG) plays an important role as a capping agent in directing growth and self-assembly of such unique structures. In addition, a certain amount of CH3COONa (NaAc) was necessary for the formation of such unique FeWO4 microstructures. The photocatalytic property of as-synthesized hierarchical FeWO4 microcrystals has been first studied, which shows excellent photocatalytic activity for the degradation of rhodamine B (RhB) under UV and visible light irradiation (modeling sunlight). Moreover, magnetic measurement indicates that hexangular FeWO4 platelike microcrystals show a small ferromagnetic ordering at low temperature because of spin-canting of antiferromagnetic materials and surface spins of FeWO4 nanoparticles.