Synthesis and Photoluminescence of Assembly-Controlled ZnO Architectures by Aqueous Chemical Growth

ZnO rod arrays were directly grown on In 2 O 3 /Sn (ITO)-coated glass substrates without needing a preprepared ZnO seed layer by aqueous chemical growth (ACG) using an equimolar aqueous solution of Zn(NO 3 ) 2 ·6H 2 O and C 6 H 12 N 4 . By further varying the substrates such as glass, Pt/glass, and Au/glass, other assembly patterns of ZnO architectures (rodlike, flowerlike, urchinlike, and stelliform crystals) were also obtained. The possible growth mechanisms for different assembly patterns dependent on the substrate were proposed. It was revealed that both the inherent highly anisotropic structure of ZnO and the surface energy minimization of different substrates play crucial roles in determining final morphologies of ZnO architectures. In addition, the photoluminescence (PL) properties of ZnO architectures on various substrates were investigated at room temperature.