Laboratory for Nanotechnology, Institute of Microsystems Engineering, Albert-Ludwigs-University Freiburg, Georges-Köhler-Allee 103, 79110 Freiburg, Germany.
Small. 2012 Nov 5;8(21):3307-14. doi: 10.1002/smll.201200841. Epub 2012 Jul 24.
A new technique is reported for the transformation of smooth nonpolar ZnO nanowire surfaces to zigzagged high-index polar surfaces using polycrystalline ZnO thin films deposited by atomic layer deposition (ALD). The c-axis-oriented ZnO nanowires with smooth nonpolar surfaces are fabricated using vapor deposition method and subsequently coated by ALD with a ZnO particulate thin film. The synthesized ZnO-ZnO core-shell nanostructures are annealed at 800 °C to transform the smooth ZnO nanowires to zigzagged nanowires with high-index polar surfaces. Ozone sensing response is compared for all three types of fabricated nanowire morphologies, namely nanowires with smooth surfaces, ZnO-ZnO core-shell nanowires, and zigzagged ZnO nanowires to determine the role of crystallographic surface planes on gas response. While the smooth and core-shell nanowires are largely non-responsive to varying O(3) concentrations in the experiments, zigzagged nanowires show a significantly higher sensitivity (ppb level) owing to inherent defect-rich high-index polar surfaces.
一种新的技术被报道用于通过原子层沉积（ALD）沉积的多晶 ZnO 薄膜将平滑非极性 ZnO 纳米线表面转化为锯齿形高指数极性表面。使用气相沉积法制造具有平滑非极性表面的 c 轴取向 ZnO 纳米线，并用 ALD 涂覆 ZnO 颗粒薄膜。合成的 ZnO-ZnO 核壳纳米结构在 800°C 下退火，将平滑的 ZnO 纳米线转变为具有高指数极性表面的锯齿形纳米线。比较了所有三种制造的纳米线形态的臭氧传感响应，即具有平滑表面的纳米线、ZnO-ZnO 核壳纳米线和锯齿形 ZnO 纳米线，以确定晶面在气体响应中的作用。虽然平滑和核壳纳米线在实验中对变化的 O3 浓度基本没有响应，但由于固有富含缺陷的高指数极性表面，锯齿形纳米线表现出更高的灵敏度（ppb 级）。
