Synthesis, characterization and photocatalytic properties of hierarchical fan-shaped ZnOHF and ZnO microcrystals

Employing NH4BF4 as the fluoride source, large scale fan-shaped ZnOHF hierarchical structures have been synthesized successfully with a template-free hydrothermal approach. The purity, crystalline phase, thermal stability and morphologies of the as-prepared ZnOHF were characterized by XRD, TG-DSC and SEM. Time-dependent experiments indicate that the hierarchical ZnOHF microfans are self-assembled by numerous nanotubes with diameter of 100 nm. A possible chemical mechanism is proposed. The as-prepared ZnOHF can be transformed into hexagonal phased netlike ZnO by calcination in air at 600 °C. Furthermore, the as-prepared ZnOHF and ZnO were investigated by the decomposition of methylene orange under UV light irradiation and the results show that they have good photocatalytic activities.

► Hierarchical fan-shaped and tubelike ZnOHF were gained with template-free hydrothermal method.
► The ZnOHF can be transformed into netlike ZnO by calcination in air at 600 °C.
► The ZnOHF and ZnO show high photocatalytic activity for the degradation of methylene orange.