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

Abstract

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.