17-08-2012, 02:11 PM
nanowires
[attachment=31852]
What are nanowires
Nanowires are microscopic wires that have a width measured in nanometers. Typically their width ranges from forty to fifty nanometers, but their length is not so limited. Since they can be lengthened by simply attaching more wires end to end or just by growing them longer, they can be as long as desired.
What Are Nanowires Made of?
Nanowires are metal just like other, regular wires. The only real difference in concept is their size. They also vary in complexity and uses. While they can do many of the same things, they have many other capabilities beyond those of regular wire.
How are nanowires made?
There are varying methods used to create nanowires. The most common involve either growing them or using DNA as a template. For the latter method, a solution containing the desired metal is mixed with DNA and then exposed to UV light. When exposed, the metal in the mixture bonds to the DNA and forms a microscopic wire, a nanowire. It’s width is dependent upon how concentrated the solution of the metal is. The more concentrated the metal solution, the wider the nanowire; likewise, the less concentrated, the thinner the wire will be.
Alternative Method?
The alternative method, growing the nanowire, uses drops of gold in precise locations on a sapphire wafer. At high temperatures the gold beads up in droplets only a few nanometers large. These droplets act as points on which zinc oxide can form crystals. The crystals grow from there and take the shape of a wire. With this method it is possible to control the direction in which the nanowire forms as well as its shape. This would make it easier to make a component such as a tiny circuit from nanowires by growing them in place instead of trying to position them in precise locations later.
[attachment=31852]
What are nanowires
Nanowires are microscopic wires that have a width measured in nanometers. Typically their width ranges from forty to fifty nanometers, but their length is not so limited. Since they can be lengthened by simply attaching more wires end to end or just by growing them longer, they can be as long as desired.
What Are Nanowires Made of?
Nanowires are metal just like other, regular wires. The only real difference in concept is their size. They also vary in complexity and uses. While they can do many of the same things, they have many other capabilities beyond those of regular wire.
How are nanowires made?
There are varying methods used to create nanowires. The most common involve either growing them or using DNA as a template. For the latter method, a solution containing the desired metal is mixed with DNA and then exposed to UV light. When exposed, the metal in the mixture bonds to the DNA and forms a microscopic wire, a nanowire. It’s width is dependent upon how concentrated the solution of the metal is. The more concentrated the metal solution, the wider the nanowire; likewise, the less concentrated, the thinner the wire will be.
Alternative Method?
The alternative method, growing the nanowire, uses drops of gold in precise locations on a sapphire wafer. At high temperatures the gold beads up in droplets only a few nanometers large. These droplets act as points on which zinc oxide can form crystals. The crystals grow from there and take the shape of a wire. With this method it is possible to control the direction in which the nanowire forms as well as its shape. This would make it easier to make a component such as a tiny circuit from nanowires by growing them in place instead of trying to position them in precise locations later.