Patterned synthesis of laterally oriented ultrafine ZnO nanowires by controlled metalorganic chemical vapour deposition

Abstract

Selective and lateral growth of ultrafine ZnO nanowires using metalorganic chemical vapour deposition (MOCVD) is studied. For selective growth of ZnO nanowires, oxidized substrates were patterned with Au layers, which serve as nucleation sites for the initial stage of ZnO nanowire growth. Electron microscopy confirmed that ultrafine ZnO nanowires with a mean diameter in the range ∼8–20 nm were rooted selectively in Au patterns and laterally extended to several micrometres on the substrate surfaces. Interestingly, nanowire bridges crosslinking the Au patterns or nanowire link-ups were frequently observed, indicating that self-organizing electrical interconnects and optical networks can be developed. Photoresponse measurements showed that exposure of the ultrafine ZnO nanowires to ultraviolet light rapidly increased the channel current from ∼150 to ∼400 nA at an applied bias voltage of 1 V.

An ambient condition, one pot route for large scale production of ultrafine (<15 nm) ZnOnanowires from commercial zinc exhibiting excellent recyclable catalytic performance: Approach extendable to CuOnanostructures

“…Together with complex process controls, sophisticated equipment and the economically prohibiting high temperature limit the application of the vapour phase transport method to a considerable degree. [6][7][8][9] On the contrary, solution phase techniques, such as hydrothermal/solvothermal processes, 10,11 aqueous homogeneous precipitations, 12,13 and electrochemical depositions, 14 are, due to their low cost, simplicity, easy scalability features, more attractive for practical use. These established chemical techniques also suffer from a number of limitations such as a low production yield (milligram scale), a quite large diameter ($100 nm or more), and toxic amines/surfactants in certain cases.…”