Controlled Growth of WO₃ Nanostructures with Three Different Morphologies and Their Structural, Optical, and Photodecomposition Studies

• Published in: Nanoscale research letters Vol. 4; no. 11; pp. 1335 - 1342
• Main Authors: Rajagopal, S, Nataraj, D, Mangalaraj, D, Djaoued, Yahia, Robichaud, Jacques, Khyzhun, O. Yu
• Format: Journal Article
• Language: English
• Published: Heidelberg New York : Springer-Verlag 01.11.2009; Springer Nature B.V
• ISSN: 1931-7573; 1556-276X
• DOI: 10.1007/s11671-009-9402-y

Tungsten trioxide (WO₃) nanostructures were synthesized by hydrothermal method using sodium tungstate (Na₂WO₄·2H₂O) alone as starting material, and sodium tungstate in presence of ferrous ammonium sulfate [(NH₄)₂Fe(SO₄)₂·6H₂O] or cobalt chloride (CoCl₂·6H₂O) as structure-directing agents. Orthorhombic WO₃ having a rectangular slab-like morphology was obtained when Na₂WO₄·2H₂O was used alone. When ferrous ammonium sulfate and cobalt chloride were added to sodium tungstate, hexagonal WO₃ nanowire clusters and hexagonal WO₃ nanorods were obtained, respectively. The crystal structure and orientation of the synthesized products were studied by X-ray diffraction (XRD), micro-Raman spectroscopy, and high-resolution transmission electron microscopy (HRTEM), and their chemical composition was analyzed by X-ray photoelectron spectroscopy (XPS). The optical properties of the synthesized products were verified by UV-Vis and photoluminescence studies. A photodegradation study on Procion Red MX 5B was also carried out, showing that the hexagonal WO₃ nanowire clusters had the highest photodegradation efficiency.