ZnO nanostructures

Mishra, P. Yadav, R. S. and Pandey, A. C. (2009). Starch assisted sonochemical synthesis of flower-like ZnO nanostructure. Digest.. Nano. Bios., 4,193-198. 

Pal U, Kim CW, Jadhav NA, Kang YS (2009) Ultrasound-assisted synthesis of mesoporous ZnO nanostructures of different porosities. J Phys Chem C 113(33) 14676-14680... 

Flou X, Zhou F, Sun Y, Liu W (2007) Ultrasound-assisted synthesis of dentritic ZnO nanostructure in ionic liquid. Mater Lett 61 1789-1792... 

Jung S-H, Oh E, Lee K-H, Park CG, Park W, Jeong S-H (2008) Sonochemical preparation of shape-selective ZnO nanostructures. Cryst Growth Des 8(1) 265—269... 

L.M. Kukreja et al., Variable band gap ZnO nanostructures grown by pulsed laser deposition. J. Cryst. Growth 268, 531-535 (2004)... 

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... 

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... 

Characterization techniques such as X-ray diffraction (XRD) and photoluminescence (PL) allow further investigation of as-grown ZnO nanomaterials. The XRD data, showing the ciystalline structures of the ZnO nanostructures grown on silicon substrates, are presented in Figure 12.2B. The XRD pattern of ZnO NRs indicates that these ZnO materials exhibit wurtzite structures. The pronounced peak at 26= 34.5° v hich corresponds to (0002) facet of wurtzite ZnO specifies <0001> as the preferential growth direction. In the wurtzite arrangement of ZnO crystalline structures, each cation is surrounded by four anions at the comer of a tetrahedron and... 

The capability of ZnO nanomaterials for reliable, multipurpose, and multiplexed fluorescence detection of interacting protein molecules is tested with a variety of model proteins [64]. As a proof-of-concept, different pairs of proteins are sequentially introduced to NR platforms and screened for fluorescence. The approach involving ZnO nanostructures in the enhanced fluorescence detection is then extended to identify the presence or absence of multiple protein / protein interactions on the same substrate. In some cases, microfluidic chambers made out of PDMS are used in order to carry out multiple protein interaction assays on the same ZnO NR supports. 

These features of the Raman bands of the ZnO nanostructures can be extremely powerful for the in situ identification of orientation of ZnO nanostructures employed in a converse piezoelectric actuator directly in an assembled state [45]. While their study focused on ZnO nanostructures, the authors noted that the general features (Raman bands and the waveguiding effect) described are equally applicable to other wurtzite type nanostructures and the approach suggested might serve as a universal tool for the versatile characterization of GaN, ZnS, and CdSe from the wurtzite family, which are utilized for optoelectronics, lasing, and piezoelectricity. 

Singamaneni S, Gupta M, Yang R, Tomczak M, Naik RR, Wang ZL, Tsukruk VV (2009) Nondestructive in situ identification of crystal orientation of anisotropic ZnO nanostructures. 

A highly sensitive glucose biosensor based on immobilization of glucose oxidase ( GOx) onto tetragonal pyramid-shaped (TPSP) ZnO nanostructure is prepare [164], TPSP- ZnO nanostructure exhibits favorable biocompability for facilitating the electron transfer between... 

Figure 9. AFM images of TPSP-ZnO before (A)and after(B)GOD loading.(C) Cyclic voltammograms ofTPSP-ZnO/Nafion (a), GOD/Nafion (b)GOD/spherical ZnO/ Nafion (c) and GOD/TPSP-ZnO/Nalion (d) modified in 0.1M pH 7.0 PB at 0.1 Vs" ( Reprinted from Biosensors and Bioelectronics, 24, Z. Dai, G. Shao, J. Hong, J. Bao, J. Shen, Immobilization and direct electrochemistry of glucose oxidase on a tetragonal pyramid-shaped porous ZnO nanostructure for a glucose biosensor, 1288,1289, Copyrights (2009) with permission fom Elsevier.

Fig. 2 illustrates (he room-temperature photoluminescence (PL) spectra recorded from the as-prepared ZnO colloidal solution and the ZnO nanostructure formed after deposition of the colloid on the silicon substrate. An UV band at 385 nm was detected from all ZnO products. In addition, a broad orange-red photoluminescence band centered at around 620 nm could be also observed in some materials. The UV photoluminescence peak at 385 nm is well known to be related to the exciton emission, ihe mechanism of visible emission is suggested mainly due to the present of various point defects, either extrinsic or intrinsic, which can easily form recombination centers. Photoluminescence measurements show that the deposited ZnO nanostructures have the stronger UV emission than the ZnO nanoparticles in the colloidal solutions. The better UV emission characteristic of deposited ZnO is suggested to be due to the lower defect density and oxygen vacancies in ZnO nanocrystals in the first case. Similar results have also been reported previously [8]. In addition, the aqueous surrounding can change the surface states of ZnO nanocrystals. It is well known that surface states may... 

Figure 2. Photoluminescence spectra of the as-prepared ZnO colloidal solution (a) and the deposited ZnO nanostructures (b) obtained with 330 nm excitation wavelength at room temperature.

Rath, M. C., Sunitha, Y, Ghosh, H. N., Sarkar, S. K., Mukherjee, T. 2009. Investigation of the dynamics of radiolytic formation of ZnO nanostructured Materials by pulse radiolysis. Radiation Physics and Chemistry 78 77-80. 

The generation of hydroxide ions induces a localised increase in the pH values close of the cathode where the Ztf + and OH ions react together leading to the precipitation of the ZnO nanostructures on the cathode via the following electrochemical reaction. ... 

Furthermore, R. K. Rana et al. reported a bio-inspired assembly of Ag/ AgCl/ZnO nanostructures with poly(allylaminehydrochloride) as the mineralizer for the enhaneed visible-light-driven photocatalytic activity. The as-prepared Ag/AgCl/ZnO had a spindle- and rod-like morphology along the (OOOl)direction with a width of 100-200 nm and a length of 400-700 nm (Fig. 26A). The Ag/AgCl particles were trapped in the porous... 

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