Heterostructure nanowires

Kim DW, Hwang IS, Kwon SJ, Kang HY, Park KS, Choi YJ, Choi KJ, Park JG. Highly conductive coaxial Sn02-In203 heterostructured nanowires for Li ion battery electrode. Nano Lett 2007 7 3041-3045. 

Fabrication or InP/InAs/InP core-multishell heterostructure nanowire arrays shown in Fig. 24 has been achieved by selective area metal-organic vapour phase epitaxy.1 These core-multishell nanowires were designed to accommodate a strained InAs quantum well layer in a higher band gap InP nanowire. Precise control over the nanowire growth direction and the heterojunction formation enabled the successful fabrication of the nanostructure in which all the three layers were epitaxially grown without the assistance of a catalyst. 

In a further extension of LCG growth, Lieber and coworkers and Yang and coworkers independently demonstrated the preparation of nanowires with structurally complex radial or axial heterostructures. Radial or core-shell heterostructure nanowires were formed by depositing layers on a core nanowire (Fig. 6A). Using this approach, homoepitaxial growth of B-doped Si shells on intrinsic Si and heteroepitaxial... 

Zhang, G., Wang, W., Li, X. (2008). Enhanced thermoelectric properties of coie/shell heterostructure nanowire composites. Advanced Materials, 20, 3654—3656. 

Goebl JA, Black RW, Puthussery J, Gibhn J, Kosel TH, Kuno M (2008) Solution-based II-VI core/shell nanowire heterostructures. J Am Chem Soc 130 14822-14833 Hoffmann MR, Martin ST, Choi W, Bahnemann DW (1995) Environmental applications of semiconductor photocatalysis. Chem Rev 95 69-96... 

Qiu XF, Burda C, Fu RL et al (2004) Heterostructured Bi2Se3 nanowires with periodic phase boundaries. J Am Chem Soc 126 16276-16277... 

Qian, F. Gradecak, S. Li, Y. Wen, C.-Y. Lieber, C. M. 2005. Core/multishell nanowire heterostructures as multicolor, high-efficiency light-emitting diodes. Nano Lett. 5 2287-2291. 

The fundamental physical properties of nanowire materials can be improved even more to surpass their bulk counterpart using precisely engineered NW heterostructures. It has been recently demonstrated that Si/Ge/Si core/shell nanowires exhibit electron mobility surpassing that of state-of-the-art technology.46 Group III-V nitride core/shell NWs of multiple layers of epitaxial structures with atomically sharp interfaces have also been demonstrated with well-controlled and tunable optical and electronic properties.47,48 Together, the studies demonstrate that semiconductor nanowires represent one of the best-defined nanoscale building block classes, with well-controlled chemical composition, physical size, and superior electronic/optical properties, and therefore, that they are ideally suited for assembly of more complex functional systems. 

Lauhon, L. J. Gudiksen, M. S. Wang, D. Lieber, C. M. 2002. Epitaxial core-shell and core-multi-shell nanowire heterostructures. Nature 420 57-61. 

Nanometer-Sized Electronic Devices The possible use of carbon nanotubes in nanoelectronics has aroused considerable interest. Dramatic recent advances have fueled speculation that nanotubes (SWNTs) will be useful for downsizing circuit dimensions. Because of their unique electronic properties, SWNTs can be interfaced with other materials to form novel heterostructures [156]. The simplest device one can imagine with carbon nanotubes is that involving a bend or a kink, arising from the presence of a diametrically opposite pentagon-heptagon pair. The resultant junction connects two nanotubes of different chirality and hence of different electronic structure, leading to the realization of an intramolecular device. Such a device in SWNTs is found to behave like a diode rectifier [157]. Silicon nanowire-carbon nanotube heterojunctions do indeed exhibit a rectification behavior [158]. 

Fundamental aspects of vapor-liquid-solid (VLS) semiconductor nanowire growth are presented here. The synthesis of VLS semiconductor has been extended to different reaction media and pathways from the early chemical vapor deposition (CVD) approach, including solution-liquid-solid (SLS) and supercritical fluid-liquid-solid (SFLS), laser-catalyzed growth, and vapor-liquid-solid-epitaxy. The properties of nanowires grown by these VLS embodiments are compared. In this entry, VLS growth of nanowire heterostructures and oriented and hyperbranched arrays is examined. In addition, surface passivation and functionalization are assessed, and the importance of these techniques in the progress toward VLS produced nanowire devices is detailed. 

In another conception of nanowire heterostructures with axially modulated composition, Lieber and coworkers generated nanowires with lithographically defined segments of alternating metallic NiSi and semiconducting Ni was thermally evaporated on... 

Qian, F. Li, Y. Gradecak, S. Wang, D. Barrelet, C.J. Lieber, C.M. Gallium nitride-based nanowire radial heterostructures for nanophotonics. Nano Lett. 2004, 4, 1975-1979. 

Wu, Y. Xiang, J. Yang, C. Lu, W. Lieber, C.M. Single-crystal metallic nanowires and metal/ semiconductor nanowire heterostructures. Nature 2004, 430 (6995), 61-65. 

Xu X, Chen L, Wang C, Yao Q, Feng C (2005) Template synthesis of heterostructured poly-aniline/BijTej nanowires. J SoUd State Chem 178 2163-2166... 

Tak, Y., Yong, K. 2008. A novel heterostructure of CofOJLnO nanowire array fabricated by photochemical coating method. Journal of Physical Chemistry C 112 74—79. 

Depending on the coverage. You etal. [167] have recently been successful in achieving nanodot arrays or nanowire array of Pl/ErSii heterostructures. Reactive... 

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