Facile synthesis of hierarchical WO3 nanocakes displaying the excellent visible light photocatalytic performance

Hierarchical WO3 nanocakes have been prepared by a green ultrasound-assisted solution chemical route and subsequent heating treatment process. The products have been characterized by XRD, FESEM, TEM, HRTEM, UV-vis diffuse reflectance spectra (DRS) and photoluminescence (PL) spectra. The results reveal that the as-synthesized cake-like architectures are assembled by multi-layered monoclinic WO3 nanosheets with the thickness of 20-30 nm. The band gap energies are estimated to be 2.65 eV. PL spectra shows a strong green-light emission band centered around 528 rim. A formation mechanism for WO3 nanostructures is simply proposed. More importantly, the cake-like WO3 architectures exhibit the superior photocatalytic activity according to the photodegradation of methylene blue under visible lighting. (C) 2015 Elsevier B.V. All rights reserved.