Simultaneous Synthesis of Al-Doped ZnO Nanoneedles and Zinc Aluminum Hydroxides through Use of a Seed Layer

Abstract

Al-doped ZnO nanoneedles with a tip diameter of similar to 10 nm and hexagonal zinc aluminum hydroxide were simultaneously synthesized and completely separated in one step. An aqueous solution containing metal ions (Zn(2+) and Al(3+)), in which a Zn-deposited substrate was immersed, was irradiated with microwaves. Al-doped ZnO nanoneedles (average Zn/Al molar ratio of 55.5) grew on the substrate, whereas zinc aluminum layered double hydroxides (average Zn/Al molar ratio of 2.51) grew as homogeneous precipitates in the bulk solution. The ID Al-doped ZnO nanoneedles had an average length of similar to 1.3 mu m. The length, diameter, and shape of the nanoneedles were uniform. The 2D hexagonal zinc aluminum hydroxides had lateral dimensions of 500 nm to 1.8 mu m and an average thickness of similar to 50 nm. Asymmetric partitioning of Zn and Al species was observed in the simultaneous synthesis of these nano/microcrystals