Microwave-assisted solvothermal synthesis and growth mechanism of WO3 center dot(H2O)(0.33) hierarchical microstructures

WO3 center dot(H2O)(0.33) hierarchical microstructures such as micro-nutlets, micro-flowers, and micro-discs have been successfully prepared via a facile microwave-assisted solvothermal route employing Na2WO4 center dot 2H(2)O and hydrochloric acid as precursors and disodium ethylenediaminetetraacetic (Na(2)H(2)EDTA) as a structure-directing agent. The products have been characterized by X-ray powder diffraction (XRD), energy dispersive X-ray analysis (EDS) scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The influences of reaction time, temperature, the volume ratio of water and glycerol, and the amount of Na(2)H(2)EDTA and hydrochloric acid on the morphologies have been studied in detail. A possible growth mechanism was proposed.