Nanometers

A nanometer is a unit of spatial measurement that is 10^-9 meter, or one billionth of a meter. Imagine that a meter is the size of the Earth; then a nanometer is about the size of a Ping-Pong ball compared to the Earth.  Approximately 3 to 6 atoms can fit side-by-side within a nanometer, depending on the atom type. In Nanotechnology, materials where dimensions and tolerances lie in the range of 0.1 nanometer (nm) to 100 nm play a critical role. Typical applications of nanotechnology include electronic circuits and mechanical devices.

What is Nanotechnology?

In short, Nanoscience is the study, and Nanotechnology is the exploitation, of the strange properties of materials smaller than 100 nanometers (nm) to create new useful objects. This work is made possible by being able to manipulate structures at the size-scale of the atoms.

Nanotechnology, or, as it is sometimes called, Engineering at the Molecular Level, is a multi-disciplinary area of applied science and engineering that deals with the design and manufacture of extremely small components and systems.   They are built at the molecular level of matter, are characterized by large surface areas in comparison with their volumes, and have behaviors that are governed by the laws of quantum mechanics.  In contrast, larger-scale engineered objects are built with masses large enough they could be described, starting with uniform bulk properties, according to the classical laws of physics and chemistry.

Why Nanotechnology?

A common question is, if the material units are so small, how can they be very useful? The answer depends on the application.  In some applications, nanomaterials can be added to other materials, thereby lending some of their unique properties to the overall performance of the composite object.  In this case, production of the nanomaterials must be scaled up to make enough of the additive to make the overall process significant and feasible.  In other cases, scientists and engineers are using smaller amounts of “nanoscale” materials, such as nanopowders and nanocrystals with unique properties as shown below, to create incredibly advanced and extremely capable devices and machines. Both of these kinds of developments could affect nearly every industrial sector in the future.

Why Now?

To answer this, one could first ask, “what are some of the world’s most pressing problems?” One issue would be global warming trends. Solutions include the need to better supply, store, and extend our use of sustainable energy. So, solutions must include more efficient electric storage cells and lighting, and Nanotechnology can help. Another solution involves manufactured objects – how can the materials we use to make the world’s goods be made to last longer or how can we use less?  Nanotechnology can help. Another issue is the availability of clean and safe drinking water.  Can Nanotechnology help?  Yes, indeed.  What about cleaner air?  Yes.  What about more affordable housing?  Yes, Nanotechnology can help.  In fact, many of the world’s most pressing problems may be addressed in part by solutions coming from Nanotechnology.

This is an incredibly exciting and profound era in the field of Materials Science and Engineering. At one time, it made sense to allow artificial knowledge boundaries develop.  The subjects of Materials, Chemistry, Physics, Mathematics, and Biology were devised to foster greater understandings. Now, these subject distinctions begin to blur with greater frequency. It is a time when new possibilities arise even without the word ”nano” in a name, simply because of human’s relentless push to understand and manipulate objects on ever-smaller scales and dimensions. And, we have ever greater opportunities to solve some of the world’s most pressing problems.

Many of the necessary tools have been developed to assist exploitation, such as the AFM¹, STM², SEM³, TEM⁴, and HRTEM⁵. These imaging techniques can resolve small features, some as small as an atomic position in a crystalline lattice. Breakthroughs from new discoveries, such as fullerene and carbon nanotube structures together with their understanding from quantum mechanics, make people believe they can realize the high-precision machinery required to produce smaller, lighter, stronger, cheaper, and higher-performance products.

This bottom up approach (atom-by-atom), rather than from the top down used in conventional approaches (making bulk products smaller and smaller), is also fueling the nanotechnology developments. The molecular auto-assembly of all devices is something that could be far too ambitious. But these developments are either here or are getting closer daily: human-made nano-composite materials as strong as steel but made from plastic, stain- and wrinkle-free Khakis, self-cleaning glass, faster computing, and many others.  In addition, other technologies will feed off this growth, such as ‘smart materials’ (material objects combining sensors and reaction mechanisms that respond to environmental stimuli) and ‘self-assembling materials’ (materials that build themselves by naturally assembling small units into larger useful objects).

Nanotechnology is entering a hyper-growth phase. There is significant government nanotechnology funding within the US, Europe, and Asia (about US$2.5B in 2003).  The US National Science Foundation predicts that the total global market for nanotechnology products and services will reach US$1 trillion by 2015, which represents nearly 10% of the present US gross domestic product and will require a work force of 2 million people.  Nanotechnology-related industries are expecting a revenue of US$25.6 billion by 2006. Today, the most prominent fields of nanotechnology are nanobio, nanomaterials, surfaces, electronics, IT and instrumentation. Of these, nanomaterials is presently the most lucrative and marketable segment in the United States, yet the nanobio and the instrumentation sector should begin to see commercialized applications in the years to come.

_____________________________

¹ Atomic Force Microscopy
² Scanning Tunneling Microscopy
³ Scanning Electron Microscopy
⁴ Transmission Electron Microscopy
⁵ High-Resolution (Transmission) Electron Microscopy