From Zn–Al layered double hydroxide to ZnO nanostructure: Gradually etching by sodium hydroxide

Zn–Al layered double hydroxide (LDH) was used as precursor to produce ZnO nanostructures through dissolution of aluminum hydroxide in caustic soda. The Zn–Al LDH could transform into different nanostructures of ZnO on LDH nanosheets and even pure ZnO nanorods under various NaOH concentration. The formed ZnO nanorods vertically aligned on both LDH sides. UV–vis diverse reflectance spectra show that the obtained ZnO nanorods have a band gap of approximately 3.05 eV. Such ZnO/LDH nanostructures might be used as photocatalyst in the organic pollutant decomposition.