Nanotechnology deals with the understanding and control of matter at dimensions between approximately 1 and 100 nanometers, where unique phenomena enable novel applications.
Dimensions between approximately 1 and 100 nanometers are known as the nanoscale.
Some examples to demonstrate the size of the nanoscale. ( Nanowerk) (click on image to enlarge)
The term was coined in 1974 by Norio Taniguichi of of Tokyo Science University to describe semiconductor processes such as thin-film deposition that deal with control on the order of nanometers. His definition still stands as the basic statement today: "Nano-technology mainly consists of the processing of separation, consolidation, and deformation of materials by one atom or one molecule."
Many argue that the history of nanotechnology starts with Richard Feynman's classic talk in December 1959: There's Plenty of Room at the Bottom - An Invitation to Enter a New Field of Physics:
Unusual physical, chemical, and biological properties can emerge in materials at the nanoscale. These properties may differ in important ways from the properties of bulk materials and single atoms or molecules.
The bulk properties of materials often change dramatically with nano ingredients. Composites made from particles of nano-size ceramics or metals smaller than 100 nanometers can suddenly become much stronger than predicted by existing materials-science models.
For example, metals with a so-called grain size of around 10 nanometers are as much as seven times harder and tougher than their ordinary counterparts with grain sizes in the hundreds of nanometers. The causes of these drastic changes stem from the weird world of quantum physics. The bulk properties of any material are merely the average of all the quantum forces affecting all the atoms. As you make things smaller and smaller, you eventually reach a point where the averaging no longer works.
The properties of materials can be different at the nanoscale for two main reasons:
Surface Area
Quantum Size Effects
Second, quantum effects can begin to dominate the behavior of matter at the nanoscale particularly at the lower end affecting the optical, electrical and magnetic behavior of materials. This effect describes the physics of electron properties in solids with great reductions in particle size. This effect does not come into play by going from macro to micro dimensions. However, it becomes dominant when the nanometer size range is reached.
The fascination with nanotechnology stems from these unique quantum and surface phenomena that matter exhibits at the nanoscale. They improve existing industrial processes, materials and applications in many fields and allows entirely new ones.
With regard to nanoscale materials, there are plenty of examples we could talk about here nanoparticles, quantum dots, nanowires, nanofibers, ultrathin-films, MXenes, etc.
One example, though, that is exemplary of how an 'old' material gets an exciting new life through nanoscale technologies is the element carbon.
Current applications of nanomaterials include very thin coatings used, for example, in electronics and active surfaces (such as self-cleaning windows). In most applications the nanomaterial will be fixed or embedded but in some, such as those used in cosmetics and in some environmental remediation applications, free nanoparticles are used. The ability to engineer materials to very high precision and accuracy (smaller than 100nm) is leading to considerable benefits in a wide range of industrial sectors, for instance in the production of components for the information and communication technology, automotive and aerospace industries.
A mite, less than 1 mm in size, approaching a microscale gear chain. (Image: Sandia National Laboratories)
Some 20-30 years ago, microelectromechanical systems (MEMS) emerged in industrial manufacturing in a major way. MEMS consist of any combination of mechanical (levers, springs, membranes, etc.) and electrical (resistors, capacitors, inductors, etc.) components to work as sensors or actuators. The size of today's smartphones would be impossible without the use of numerous MEMS devices. Apart from accelerometers and gyroscopes, smartphones contain micro-mirrors, image sensors, auto-focus actuators, pressure sensors, magnetometers, microphones, proximity sensors and many more. Another example from everyday life is the use of MEMS as accelerometers in modern automobile airbags where they sense rapid deceleration and, if the force is beyond a programmed threshold, initiate the inflation of the airbag.
Then, researchers took a further step down the size scale and have begun exploring another level of miniaturization nanoelectromechanical systems (NEMS). NEMS are showning great promise as highly sensitive detectors of mass, displacement, charge, and energy.
In some senses, nanoscience and nanotechnologies are not new. Chemists have been making polymers, which are large molecules made up of nanoscale subunits, for many decades and nanotechnologies have been used to create the tiny features on computer chips for the past 30 years.
However, advances in the tools that now allow individual atoms and molecules to be examined and probed with great precision have enabled the expansion and development of nanoscience and nanotechnologies. With new tools came new fundamental concepts and it turned out that the mechanical rules that govern the nanoworld are quite different from our everyday, macroworld experience.
Today there are a number of tools that can be used to characterize the nanomechanics of biomolecular and cellular interactions. Besides cantilever-based instruments like the AFM, examples include optical tweezers, and magnetic pullers.
Nano tech improves existing industrial processes, materials and applications by scaling them down to the nanoscale in order to ultimately fully exploit the unique quantum and surface phenomena that matter exhibits at the nanoscale. This trend is driven by companies' ongoing quest to improve existing products by creating smaller components and better performance materials, all at a lower cost.
A prime nanotechnology example of an industry where nanoscale manufacturing technologies are employed on a large scale and throughout is the semiconductor industry where device structures have reached the single nanometers scale. Your smartphone, smartwatch or tablet all are containing billions of transistors on a computer chip the size of a finger nail.
So, what can nanotechnology do? There is almost no field today where nanotechnology isn't applied in some form or shape as things like surface coatings, sensors, electronic components, membranes, etc. in medicine, environmental remediation, water filtration, nanoelectronics, food and agriculture, cosmetics, energy and batteries, space and aeronautics, automotive industries, displays, sports equipment and many more.
If you select "Introduction to Nanotechnology" from our menu bar above you will find numerous articles on all these topics in the right column.
Many products are defined as "nanotechnology product" because they contain nanoparticles in some form or other. For instance, many antimicrobial coatings contain silver in nanoscale form; food products and cosmetics contain nanoparticles; and some products are partially made with composite materials containing nanomaterials (e.g. carbon nanotubes or -fibers) to mechanically strengthen the material.
"Nanotech" products that are on the market today are mostly gradually improved products (using evolutionary nanotechnology) where some form of nano-enabled material (such as carbon nanotubes, graphene, nanocomposite structures or nanoparticles of a particular substance) or nanotech process (e.g. nanopatterning or quantum dots for medical imaging) is used in the manufacturing process.
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Nanotechnology - Definition and Introduction - Nanowerk
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