ZnO nanowire

Fan HJ, Barnard AS, Zacharias M (2007) ZnO nanowires and nanobelts Shape selection and thermodynamic modeling. Appl Phys Lett 90 143116-143119... 

Ju, S. Lee, K. Yoon, M.-H. Facchetti, A. Marks, T. J. Janes, D. B. 2007. High performance ZnO nanowire field effect transistors with organic gate nanodielec-... 

Figure 10.17. (a) Schematic diagram of the nanowire dye-sensitized solar cell. Light is incident through the bottom electrode, (b) SEM cross section of a solution-fabricated ZnO nanowire array on fluorine-doped tin oxide. The wires are in direct contact with the substrate. Scale bar, 5 pm. Reproduced from Ref. 41, Copyright 2005, with permission from the Nature Publishing Group. 

Solution-grown zinc oxide nanowires by Greene etal. (2006). Strategies for growing ZnO nanowires from zinc salts in aqueous and organic solvents are reviewed. 

Fig. 5.20 SEM images of ZnO nanowires grown on graphene via CVD from a solid Zn precursor at increasing growth times from (a) 5 min to (b) 10 min and (c) 15 min, insets show higher magnification SEM images of the same surfaces. Reprinted with permission from [243], (2012) Elsevier.

Hwang, ).0., et al., Vertical ZnO nanowires/graphene hybrids for transparent and flexible field emission. Journal of Materials Chemistry, 2011. 21(10) p. 3432-3437. 

Possible applications of ZnO nanostructures are UV lasers (up to now only with optical excitation) [84], chemical sensors [85], or transparent substrates for thin film solar cells, e.g. as an alternative to Ti02 in injection type solar cells or in organic solar cells [79,86,87]. In the latter two applications the increased effective surface of arrays of ZnO nanowires leads to... 

Fig. 1.9. Plain view (left) and cross-sectional view (right) of ZnO nanowires prepared from a chemical solution on a magnetron-sputtered ZnO film on fluorine-doped Sn02 on glass, which are used as a substrate for dye-sensitized solar cells [79]...

In this section advanced developments of the PLD technique are shortly described, e.g., the combinatorial approach and laser MBE. Because of the increasing research interest in ZnO-based nanostructures, the established PLD (at background gas pressure 10-4—3 mbar) was extended to much higher pressures of 50-200 mbar to grow arrays of free-standing ZnO nanowires. This unique high-pressure PLD process allows the growth of ZnO-based nanostructures with controlled shape and diameter and excellent optical properties. 

Fig. 7.33. Typical SEM images of PLD grown ZnO nanowires (lOOmbar Ar, 840° C) on a-plane sapphire with Au colloides as nucleation sites [142]...

I-D ZnO nanostructures have been synthesized by oxygen assisted thermal evaporation of zinc on a qdartz surface over a large area.191 Pattern- and feature-designed growth of ZnO nanowire arrays for vertical devices has been accomplished by following a pre-designed pattern and feature with controlled site, shape, distribution and orientation.192... 

Kong, Y.C., D.P. Yu, B. Zhang, W. Fang and S.Q. Feng (2001). Ultraviolet-emitting ZnO nanowires synthesized by a physical vapor deposition approach. Applied Physics Letters, 78(4), 407 109. 

Li, Y., G.W. Meng, L.D. Zhang and F. PhiUipp (2000). Ordered semiconductor ZnO nanowire arrays and their photoluminescence properties. Applied Physics Letters, 76(15), 2011-2013. 

Figure 2. Different shapes of PLD grown ZnO micro- and nanocrystals, (a) Hexagonal microcrystals with diameters of about 2 pm. (b) ZnO nanowires with diameters around 100 nm. (c) Needle like nanostructures, (d) Microcrystals exhibiting a dodecagonal cross section.

An example of polarity determination and its application is the study of the growth mechanism of ZnO nanowires. During ZnO growth, asymmetric side growth is... 

Gao, P. X., and Wang, Z. L. (2004). Substrate atomic-termination-induced anisotropic growth of ZnO nanowires/nanorods by the VLS process. J. Phys. Chem. B 108 7534-7537. 

C. The ZnO nanowire templates were subsequently removed by thermal reduction and evaporation, resulting in ordered arrays of GaN nanotubes on the substrates. 

It is clear from the VLS nanowire growth mechanism that the positions of the nanowires can be controlled by the initial positions of the Au clusters or Au thin films. By creating desired patterns of Au using the lithographic technique it is possible to grow ZnO nanowires of the same designed pattern since they grow... 

An ordered array of ZnO nanowires on alumina membranes was prepared by oxidizing electrodeposited Zn nanowires in air at 300 °C. The electrodeposition was carried out from an acidic bath of ZnS04-7H20 (0.3 M Boric acid and 0.28 M ZnS04-7H20). The grown nanowires showed PL at 55 nm. 

Baxter J. B. and AydU E. S. (2006), Dye-sensitized solar cells based on semiconductor morphologies with ZnO nanowires . Solar Energy Mat. Solar Cells 90, 607-622. 

Greene LE, Law M, Tan DH, Montano M, Goldberger J, Somorjai G, Yang P (2005) General route to vertical ZnO nanowire arrays using textured ZnO seeds. Nano Lett 5 1231... 

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