Morphology controlled growth of ZnAl-layered double hydroxide and ZnO nanorod hybrid nanostructures by solution method

Abstract

We report the morphological evolution of ZnAl-based hybrid nanostructures from ZnAl layered double hydroxide (LDH) to ZnO nanorods (NRs) grown by a hydrothermal method depending on the thickness of the Al₂O₃/ZnO double seed layer. The thickness of the Al₂O₃/ZnO double seed layer was controlled by an atomic layer deposition system. We found that the ZnAl-LDH growth can mainly be attributed to the hydroxide reactions between the base solution and Al₂O₃ as a sacrificial layer. As the ZnO seed layer covered the Al₂O₃ film, the concentration of Al hydroxide was significantly reduced, but that of the Zn hydroxide increased enough to make ZnO NRs. Our results show that hybridizing these ZnAl-LDH and ZnO NRs by controlling the amount of Al cations is possible, and thus we can design a new material system by taking advantage of the unique properties of ZnAl-LDH and ZnO NRs for future applications.