For almost two years, I've used this column to help give you a clear mental image of what nanotechnology is and what it can do.
This month, we're going literal -- with the help of amazing images from NanoSurf, Inc., a maker of atomic force microscopes (www.nanosurf.com).
Believe me, it's more than pretty pictures. Once you take a closer look, it's easier to understand nanotechnology and imagine how to put it to work.
Let's start with a carbon nanotube. It's just like it sounds like -- a flat sheet of carbon atoms that is rolled into a hollow tube. They can be single-walled or double-walled and are generally 10 times longer than their diameter. And what's the magic? Carbon nanotubes are among the strongest materials on earth (think body armor or super-strong building materials), and they also exhibit electrical properties that can exponentially increase the power of ever-smaller computers.
Nanofibers are another area of intense interest. They look like the fibers in paper or felt, don't they? Nanofibers can be spun of many substances, each supplying its own benefit. They can provide filtering, absorbency or added strength. They've also been used to improve clotting for wound bandaging and high-density energy storage.
A look at the nano-world also helps focus on needs that nanotechnology can address. Take a look at an airplane wing. See the nanoscale ridges and valleys? Those nanoscale grooves allow ice molecules a firmer grip on the wing's surface and that's the reason you have to sit on airport runways for de-icing on winter days. A number of researchers are working on icephobic coatings that, among other traits, could fill those gaps or make them too "slippery" for ice to take hold.
The problems (and solution) facing aeronautics have a parallel in plastics we use in our everyday lives. You can see it here in the polished surface of an eyeglass lens. In this case, coatings that provide anti-reflective benefits or tints are put onto the peaks and valley that remain in a lens. The coatings on the peaks are more likely to get scraped away or damaged. A durable nanocoating can protect the active coatings underneath, in part because they fill in the valleys to create a more regular surface that is less susceptible to damage.
Those same issues of surface irregularity are an issue with CDs. The irregular surface you see here can make data susceptible to bring scraped off. What's more annoying that a music CD that "skips" or a data CD that becomes inaccessible? A nanocoating, oftentimes infused with nanoparticles, can help protect and preserve the CD content.
Here's another susceptible surface that we can all find in our own kitchens -- ceramic. The photo here is of a dental ceramic (unpolished on the top, polished on the bottom). The same irregularity seen here is also present in ceramic cookware or tableware. That irregularity provides more surface area for chemicals or environmental pollutants to break down the material. If it's cookware, food may be more likely to stick to it. A nanocoating can potentially block contaminants making the surface easier to clean and the product longer lasting.
A nanofilm often offers the benefit of being more strongly bonded to the surface of a substrate, rather than just being "painted on." That's because these films self-assemble on the surface, which means the molecules line up, cross link with other molecules, and bind to the substrate. You can see that strict grid pattern in the photo here. The result? A surprisingly strong and durable film that's so thin it's invisible.
Let's finish up with a nano-picture of the future of energy: the quantum dot. First, we need some background. If you have a one-foot cube of a material, it has the same properties as a one-inch cube, or a one-millimeter cube. However, as the size becomes smaller and smaller -- down to the nanoscal -- very different properties emerge. For quantum dots, it allows for creation of materials that absorb and fluoresce light at size-specific wavelengths. In an LED, it lets you choose the color of the light being emitted. In biological testing, it provides an easy-to-read marker. In solar panels, it's at the core of an approach to energy collection. Currently, solar panels capture only a narrow bandwidth of light, depending on the absorbing material used. Researcher hope that by using quantum dots of different materials in the panels, more wavelengths of light can be captured. In one calculation, quantum dot technology could capture energy from 70% of sunlight's wavelengths versus less than 10% in current technology.
So, do you get the picture? When you look closely, it's easier to understand the need for nanotechnology - and the solutions it can provide. Want to see more? Nanosurf has a fascinating image gallery at www.nanosurf.com. It includes images of Martian dust particles taken by a NanoSurf AFM aboard NASA's Phoenix Mars Rover. And come back next month when we'll do more visioning about nano-izing your company and products.
Scott E. Rickert is chief executive of Nanofilm, Ltd, located in Valley View, Ohio.
