Microwave hydrothermal synthesis and optical properties of flower-like Bi2MoO6 crystallites

Flower-like Bi2MoO6 crystallites were successfully synthesized by the microwave hydrothermal process using Bi(NO3)3·5H2O and Na2MoO4·2H2O as source materials and adding hexamethylene tetramine (HMT) as a template. X-ray diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM) were used to characterize the products. Ultraviolet-visible (UV-vis) spectroscopy was employed to study the optical properties of Bi2MoO6. Results show that the product morphology is flower-like on adding the template. These flower-like Bi2MoO6 crystallites are a self-assembly of many thin nanoplates. HMT plays an important role in the formation of the flower-like morphology. UV-vis absorption spectra of all the Bi2MoO6 samples show strong photoabsorption properties from the ultraviolet region to the visible-light region with wavelength shorter than 500 nm. The band gap of flower-like Bi2MoO6 crystallites displays a slight red-shift compared with the Bi2MoO6 plate-like structures.