Face-selective tungstate ions drive zinc oxide nanowire growth direction and dopant incorporation

Abstract

Tailoring the elemental doping of inorganic nanowires remains an important challenge due to complex dopant incorporation pathways. Here we report that the face-selectivity of tungstate ions controls growth direction and dopant incorporation of hydrothermal zinc oxide nanowires. The introduction of tungstate ions on nanowire surface during synthesis unexpectedly enhances nucleation at sidewall 10 10 f g planes, while dopant incorporation occurs only on (0001) planes. This conflicting face-selective behavior leads to inhomogeneous dopant distribution. Density functional theory calculations reveal that the face-selective behavior can be interpreted in terms of the effect of coordination structure of the tungstate ions on each zinc oxide crystal plane. In addition, we demonstrate a rational strategy to control the morphology and the elemental doping of tungsten-doped zinc oxide nanowires.

Robust and Electrically Conductive ZnO Thin Films and Nanostructures: Their Applications in Thermally and Chemically Harsh Environments

“…Various fabrication methods have been investigated to obtain high-quality ZnO thin films and nanostructures on substrates. These methods can be classified into the following three types: − (a) physical vapor deposition, including thermal evaporation, molecular beam epitaxy, sputtering, and laser ablation; − (b) chemical vapor deposition (CVD), including metal–organic CVD, mist CVD, hot filament CVD, and atomic layer deposition; ,, (c) chemical solution synthesis including sol–gel synthesis, hydrothermal growth, and spray pyrolysis. − Generally, the parameters of these synthesis methods are optimized to obtain ZnO thin films and nanostructures with the required physical and chemical properties, high stability, and compatibility using various substrates. However, parameter optimization generally involves a trade-off between the required properties.…”

“…Hydrothermal synthesis has been intensively investigated for the fabrication of nanostructures at low temperatures for applications such as light-emitting devices, solar cells, and sensors. ,,, In the hydrothermal growth of ZnO nanostructures, several parameters, including the pH of growth solutions, temperature, and ionic species, should be optimized to obtain the desired morphology and properties. Understanding the effects of these parameters is crucial for fabricating ZnO nanostructures to be used in harsh electronics. ,,, …”

Moderate molecular recognitions on ZnO m-plane and their selective capture/release of bio-related phosphoric acids

“…Thus, ZnO NWs and nanowalls provide unique face-selective electrostatic interactions by anisotropic crystal growth. 26,[59][60][61][62][63] and the long columnar shape (Fig. S2 †) implied abundant mplanes.…”

Tailoring ZnO nanowire crystallinity and morphology for label-free capturing of extracellular vesicles

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