nano

Nano! Part 2

/ Amanda / Leave a comment

Good morning and happy Friday!

It’s time for another round of lessons in the NANOWORLD!! (everyone cheers)

If you missed the intro post, you can find it here. Now, onto more cool nano-tech.

If you recall, nano is a scientific prefix that refers to something on the order of 10^-9 or 0.000000001 units. Today we’re going to talk about the size aspects of the nano-scale. There are different ways that a material can be considered ‘nanoscale’.

There are 1D structures like nanofibers, nanowires, basically think tubes or cylinders. What makes them nano is the diameter of the tube/wire/fiber/cyliner is nanoscale. Think, 90 nanometers (nm) in diameter. They are not necessarily nanoscale in length. You can have a nanowire that is 90 nanometers is diameter and is 350 microns long (or 10^-6 meters or 0.000001 meters long). This is a pretty big aspect ratio. Which is one reason why materials on the nanoscale have different behaviors and characteristics than their bulk counterparts.

nanowires_hairy_solar_cell

Image from research.che.tamu.edu

 

I’m sure you can see where this lesson is going….so there are 2D nanostructures as well! Things like nanoflakes, nanosheets…like a sheet of paper only nano! Graphene, which we talked about last time, is a good example of a 2D nanostructure. Like with the 1D nanostructures, the nano doesn’t refer to all dimensions. In this case, the thickness is typically considered nanoscale. The length and width of the sheet aren’t necessarily nano.

The last dimension that we haven’t talked about yet is 3D!

3dglasses

No worries, you don’t need 3D glasses for this part. 3D nanostructures include spheres, cubes, pyramids, diamond shapes….the possibilities are endless! The picture shows some nanospheres. These spheres have a nanoscale diameter and….well…I think you get the gist of it now so just admire the picture and how perfectly aligned all the spheres are. (sighs contentedly)

Different nano structures have different properties. For instance….a silver nanowire will not necessarily have the same properties as a silver nanosphere. Same element. Different structure. Different properties. The applications are endless! Pretty cool 🙂

 

 

 

 

Nano! Part 1

/ Amanda / 1 Comment

Good morning! I’m feeling pretty exhausted today but I figured you all ought to know about what ‘nano’ is since chances are it’ll get talked about quite a bit on the blog. So brace yourselves. It’s about to get sciency up in here!

Nano is a prefix that means something is 10^-9 or 0.000000001 units (I think that’s the right number of 0’s, I kinda lost count) of something aka suuuuper tiny shit. Usually you hear it used in reference to size (i.e. nanometer). We are talking about things that are only slightly (an order of magnitude for you sciency folks) larger than an atom. Here’s a pretty useful infographic about size.

http://www.asu.edu/clas/csss/NUE/img/Scale-of-Things.jpg – always cite your sources people!

Basically you can look at individual atoms on the nano-scale. Pretty nifty right??

So why do we care? Besides the cool factor. Well materials and shit behave differently when you shrink them down. For example, gold. Everything shown in the image below is pure gold. So why are the vials not gold-colored?

http://blog.manuscriptedit.com/wp-content/uploads/2014/01/Fig-1-gold-macro-vs-nano1.png More citations y’all. Seriously, don’t plagiarize.

Great question! It’s because those vials contain gold nanoparticles in a clear solution. At this the macro scale, gold reflects light along a yellow wavelength. At the nano scale it reflects red! Same material. Different properties!

This doesn’t just go for color. Nanoscale materials have all sorts of different properties than their bulk counterparts. There’s a reason for it, but I won’t go into that today since this is a butt-load of info already.

Right now I’m working with graphene. Sounds like graphite (the stuff in pencils) right? They’re the same material at different sizes. Graphite is a bunch of layers of carbon atoms in a particular pattern (they make hexagons or if you want to sound like a pro – they have a hexagonal lattice). Graphene is basically less than 5 layers of graphite. This pic is one layer of graphene.

http://en.wikipedia.org/wiki/Graphene#mediaviewer/File:Graphen.jpg

Let’s be honest, graphite is not the most exciting material. But when you strip it down to graphene it gets super exciting. It’s crazy strong (100 times stronger than steel by weight), and is both thermally and electrically conductive.

This material was first isolated in 2004 which led to the guys getting a Nobel Prize (“The Nobel Prize in Physics 2010”. The Nobel Foundation.) <—citations y’all. Aka it was a pretty big deal. Also this is a pretty new material. There is a whole world of applications and uses for graphene that are basically the latest and greatest thing to research right now.

  • Flexible touch screens
  • Drug delivery systems
  • Structural supports
  • The sky’s the limit!

What would you use graphene for?