Nanotechnology

Nanotechnology is the science of working with very, very tiny pieces of matter—so small that you can only see them with special microscopes. These pieces are measured in nanometers, which are billionths of a meter. At this size, materials can behave in surprising ways, very different from larger objects we see every day.

Fullerene nanogears

This field brings together many areas of science and engineering, like chemistry, biology, physics, and materials science. Researchers use nanotechnology to create new substances and inventions, such as better medicines, faster computers, and stronger materials for everyday products.

While nanotechnology holds great promise for improving many parts of our lives, it also raises important questions. Scientists are carefully studying how these tiny materials might affect our health and the environment, and some people are discussing whether special rules are needed to make sure nanotechnology is used safely.

Origins

Main article: History of nanotechnology

Comparison of nanomaterials sizes

Nanotechnology began with ideas from physicist Richard Feynman in 1959, who talked about moving atoms around to build tiny things. The word "nanotechnology" was first used in 1974 by Norio Taniguchi, but it became well-known in 1986 when K. Eric Drexler wrote a popular book about it.

In the 1980s, new tools like the scanning tunneling microscope let scientists see and move individual atoms. Important discoveries, such as buckminsterfullerene and carbon nanotubes, helped grow the field. Governments started supporting nanotechnology research, leading to many new products and scientific studies.

Fundamental concepts

Nanotechnology is the science and engineering of working with things at the molecular scale. It involves making and using tiny structures and machines that are so small they can only be seen with special tools.

Image of reconstruction on a clean Gold(100) surface, as visualized using scanning tunneling microscopy. The positions of the individual atoms composing the surface are visible.

One nanometer (nm) is one billionth of a meter, or 10⁻⁹, of a meter. This is very small — for example, the diameter of a DNA molecule is about 2 nanometers, and tiny bacteria are around 200 nanometers long. Nanotechnology works with sizes from 1 to 100 nanometers, where special properties of materials appear that aren't seen in bigger objects.

There are two main ways to build things in nanotechnology. In the "bottom-up" approach, tiny parts come together on their own, like building blocks finding their place. In the "top-down" approach, scientists start with bigger pieces and shape them into nanoscale devices. These tiny structures can have very different properties than larger pieces of the same material, making them useful for many advanced technologies.

Research

Graphical representation of a rotaxane, useful as a molecular switch

Nanotechnology is the study of very tiny materials and structures, usually between 1 and 100 nanometers in size. At this scale, materials can have special properties that larger materials do not have.

Many areas of science study materials with unique properties because of their tiny sizes. These nanomaterials can be used in many ways, such as in medicine for delivering drugs or in solar cells to help create energy. Scientists use different methods to build these tiny structures, either by putting small parts together or by shaping larger materials into smaller forms. These tiny materials and devices have many possible uses in technology and medicine.

Tools and techniques

Typical AFM setup. A microfabricated cantilever with a sharp tip is deflected by features on a sample surface, much like in a phonograph but on a much smaller scale. A laser beam reflects off the backside of the cantilever into a set of photodetectors, allowing the deflection to be measured and assembled into an image of the surface.

The atomic force microscope and the scanning tunneling microscope are special tools that help scientists see and work with tiny things, even smaller than the width of a human hair. These tools have very sharp tips that can touch and move around tiny particles.

Scientists also use different methods to create tiny structures. Some methods shape materials from the top down, like using tiny stamps to make patterns. Other methods build structures from the bottom up, adding atoms one by one, much like building with Lego blocks. These techniques help make new materials and devices for many uses, including in medicine.

Applications

Main article: List of nanotechnology applications

One of the major applications of nanotechnology is in the area of nanoelectronics with MOSFETs being made of small nanowires ≈10 nm in length. Here is a simulation of such a nanowire.

Nanotechnology has many useful applications. By August 2008, over 800 products using nanotechnology were available, with new ones appearing every few days. These products include sunscreen, cosmetics, and food that use special materials like titanium dioxide. Nanotechnology is also used in clothing to make it last longer and stay cool in summer, and in bandages with silver to help cuts heal faster.

In cars, nanotechnology helps make batteries better and last longer. It can also make sports equipment like tennis balls and golf balls perform better. Computers and video game consoles might become faster and cheaper thanks to nanotechnology. In medicine, nanotechnology helps deliver drugs more effectively and can even help create new tissues in the body. These tiny tools are making many areas of life better and more efficient.

Implications

Main article: Implications of nanotechnology

Nanotechnology involves working with very tiny particles, which can have special properties. Some people worry about how these tiny particles might affect our health and the environment if they are used widely in factories and products. Researchers are studying these possible effects to make sure we stay safe.

There are concerns that tiny particles used in products, like those in socks, might accidentally harm nature when they end up in wastewater. Some studies in animals have shown that breathing in these tiny particles can cause problems in the lungs and other health issues. This is why some experts think careful rules and more research are needed before using nanotechnology in many products.

Regulation

Main article: Regulation of nanotechnology

There have been discussions about the need for better rules to keep nanotechnology safe for people and the environment. Some groups have pointed out that current laws don’t fully cover all parts of nanotechnology, which leaves gaps in safety measures. Experts have suggested more research and careful steps to make sure products are safe before they hit the market. One report suggested that companies should clearly explain how they will handle products at the end of their life to reduce any possible risks to people or nature.