Rapid synthesis of aligned zinc oxide nanowires

Ünalan, Hüsnü Emrah
Rupesinghe, Nalin
Dalal, Sharvari
Milne, William I.
Amaratunga, Gehan A. J.
A solution growth approach for zinc oxide (ZnO) nanowires is highly appealing because of the low growth temperature and possibility for large area synthesis. Reported reaction times for ZnO nanowire synthesis, however, are long, spanning from several hours to days. In this work, we report on the rapid synthesis of ZnO nanowires on various substrates (such as poly(ethylene terephthalate) (PET), silicon and glass) using a commercially available microwave oven. The average growth rate of our nanowires is determined to be as high as 100 nm min(-1), depending on the microwave power. Transmission electron microscopy analysis revealed a defect-free single-crystalline lattice of the nanowires. A detailed analysis of the growth characteristics of ZnO nanowires as functions of growth time and microwave power is reported. Our work demonstrates the possibility of a fast synthesis route using microwave heating for nanomaterials synthesis.


Direct measurement of charge transport through helical poly(ethyl propiolate) nanorods wired into gaps in single walled carbon nanotubes
Wang, Nan; Yano, Koji; Durkan, Colm; Plank, Natalie; Welland, Mark E.; Zhang, Yan; Ünalan, Hüsnü Emrah; Mann, Mark; Amaratunga, G. A. J.; Milne, William I. (IOP Publishing, 2009-03-11)
We report the direct measurement of electrical transport through rod-like polymer molecules, of poly(ethyl propiolate) (PEP), utilizing single walled carbon nanotubes (SWNTs) as electrodes. The electrical properties of the devices were measured (i) before cutting a SWNT, (ii) when a SWNT was cut and (iii) after PEP deposition into the nanoscale gap in a cut SWNT. The gate-dependent electrical properties showed a reduction in current from I-on = 2.4 x 10(-7) A for SWNT devices to I-on = 3.6 x 10(-9) A for PE...
Effect of electroless etching parameters on the growth and reflection properties of silicon nanowires
Ozdemir, Baris; Kulakci, Mustafa; Turan, Raşit; Ünalan, Hüsnü Emrah (IOP Publishing, 2011-04-15)
Vertically aligned silicon nanowire (Si NW) arrays have been fabricated over large areas using an electroless etching (EE) method, which involves etching of silicon wafers in a silver nitrate and hydrofluoric acid based solution. A detailed parametric study determining the relationship between nanowire morphology and time, temperature, solution concentration and starting wafer characteristics (doping type, resistivity, crystallographic orientation) is presented. The as-fabricated Si NW arrays were analyzed ...
Nanowire decorated, ultra-thin, single crystalline silicon for photovoltaic devices
AURANG, Pantea; Turan, Raşit; Ünalan, Hüsnü Emrah (IOP Publishing, 2017-10-06)
Reducing silicon ( Si) wafer thickness in the photovoltaic industry has always been demanded for lowering the overall cost. Further benefits such as short collection lengths and improved open circuit voltages can also be achieved by Si thickness reduction. However, the problem with thin films is poor light absorption. One way to decrease optical losses in photovoltaic devices is to minimize the front side reflection. This approach can be applied to front contacted ultra-thin crystalline Si solar cells to in...
Optimization of silver nanowire networks for polymer light emitting diode electrodes
Coskun, Sahin; Ates, Elif Selen; Ünalan, Hüsnü Emrah (IOP Publishing, 2013-03-29)
Silver nanowire (Ag NW) networks are promising candidates for replacement of indium tin oxide (ITO). However, transparent conductors based on Ag NW networks often suffer from 'haziness' resulting from surface roughness. Thus, in addition to achieving suitable transparency and conductivity, surface roughness must be minimized if realistic implementation of Ag NW networks as transparent conductors is to be realized. In this work, we have reduced the surface roughness of Ag NW networks to below 5 nm as compare...
Growth and process conditions of aligned and patternable films of iron(III) oxide nanowires by thermal oxidation of iron
Hiralal, P.; Ünalan, Hüsnü Emrah; Wijayantha, K. G. U.; Kursumovic, A.; Jefferson, D.; MacManus-Driscoll, J. L.; Amaratunga, G. A. J. (IOP Publishing, 2008-11-12)
A simple, catalyst-free growth method for vertically aligned, highly crystalline iron oxide (alpha-Fe2O3) wires and needles is reported. Wires are grown by the thermal oxidation of iron foils. Growth properties are studied as a function of temperature, growth time and oxygen partial pressure. The size, morphology and density of the nanostructures can be controlled by varying growth temperature and time. Oxygen partial pressure shows no effect on the morphology of resulting nanostructures, although the oxide...
Citation Formats
H. E. Ünalan, N. Rupesinghe, S. Dalal, W. I. Milne, and G. A. J. Amaratunga, “Rapid synthesis of aligned zinc oxide nanowires,” NANOTECHNOLOGY, pp. 0–0, 2008, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/37612.