Investigation of γ-AlOOH and NiWO4-coated boehmite micro/nanostructure under UV/visible light photocatalysis

A large-scale boehmite (γ-AlOOH) sphere and NiWO 4 -coated boehmite micro/nanostructured materials were synthesized via a facile two-step hydrothermal method with microwave irradiation using a solution phase route. The morphologies and structures of the prepared samples were characterized by scanning electron microscopy, high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction, Fourier transform infrared spectroscopy, and energy-dispersive X-ray spectroscopy, and their optical and photocatalytic properties were also measured. The samples boehmite, AN1 and AN2 (different concentrations by NiWO 4 ) were evaluated under UV/visible-light irradiation, and the AN1 sample showed intense (92.6%) degradation of methyl blue dye of the three samples. This enhancement was explained reasonably by HR-TEM evaluated surface-coated core–shell structured γ-AlOOH@NiWO 4 shell width was about 10–15 nm and the core–shell size 120 nm. From the optical analysis, the core–shell heteronanostructure new energy level was attributed to the synergistic effect between NiWO 4 and boehmite. In particular, a down-conversion luminescence process at the 450 nm excited energy optimization of redox for the efficient photogeneration of electron–hole pairs. Additionally, trapping measurement showed that O 2 · − and OH· species generated in the photocatalytic process played a key role in the degradation reaction. Based on these findings, this approach may offer a new strategy for the fabrication of surface-controlled spheres of core/shell structure-based photocatalysts with enhanced efficiency for environmental remediation applications.