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

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.