Nanomaterials is the study of how materials behave when their dimensions are reduced to the nanoscale. It can also refer to the materials themselves that are used in nanotechnology. Buckminsterfullerene C60, also known as the buckyball, is the simplest of the carbon structures known as fullerenes. ... Image File history File links Download high resolution version (672x623, 147 KB)A 3D model of a C60 molecule, also called a Buckyball. Created by Michael Ströck (mstroeck) on February 6, 2006 in iMol for Mac OS X and Photoshop CS2. ... Nanotechnology reaches back to the late 19th century, when colloidal science first took root. ... Groups opposing the installation of nanotechnology laboratories in Grenoble, France, have spraypainted their opposition on a former fortress above the city Potential risks of nanotechnology can broadly be grouped into three areas: the risk to health and environment from nanoparticles and nanomaterials; the risk posed by molecular manufacturing (or advanced... This article or section does not cite its references or sources. ... This is a list of organizations involved in nanotechnology. ... This is a list of references and appearances of Nanotechnology in works of fiction. ... This page aims to list all topics related to the field of nanotechnology. ... Nanomedicine is the medical application of nanotechnology. ... An example of a molecular self-assembly through hydrogen bonds reported by Meijer and coworkers in Angew. ... Molecular electronics (sometimes called moletronics) is a branch of applied physics which aims at using molecules as passive (e. ... Scanning probe microscopy (SPM) is a branch of microscopy that forms images of surfaces using a physical probe that scans the specimen. ... Nanolithography — or lithography at the nanometer scale — refers to the fabrication of nanometer-scale structures, meaning patterns with at least one lateral dimension between the size of an individual atom and approximately 100 nm. ... Molecular nanotechnology (MNT) is the concept of engineering functional mechanical systems at the molecular scale. ... The Icosahedral Fullerene C540 C60, C-60 and Buckyballs redirect here. ... 3D model of three types of single-walled carbon nanotubes. ... Fullerene chemistry is a field of organic chemistry devoted to the chemical properties of fullerenes [1] [2] [3]. Research in this field is driven by the need to functionalize fullerenes and tune their properties. ... Carbon nanotubes have many potential applications, here is a short list of some of the most important: // clothes: waterproof tear-resistant cloth fibers combat jackets: MIT is working on combat jackets that use carbon nanotubes as ultrastrong fibers and to monitor the condition of the wearer. ... Examples of fullerenes in popular culture are numerous. ... Timeline of carbon nanotubes: Inside a carbon nanotube 1952 Radushkevich and Lukyanovich publish a paper in the Russian Journal of Physical Chemistry showing hollow graphitic carbon fibers that are 50 nanometers in diameter. ... This article or section does not cite any references or sources. ... It has been suggested that nanopowder be merged into this article or section. ... A quantum dot is a semiconductor nanostructure that confines the motion of conduction band electrons, valence band holes, or excitons (bound pairs of conduction band electrons and valence band holes) in all three spatial directions. ... Colloidal gold is a suspension (or colloid) of sub-micrometre-sized particles of gold in a fluid, usually water. ... Colloidal silver is a colloid of silver particles in water. ... A molecular assembler is a molecular machine capable of assembling other molecules given instructions, energy, and a supply of smaller building block molecules to work from. ... It has been suggested that this article or section be merged with mechanochemistry. ... Nanorobotics is the technology of creating machines or robots at or close to the scale of a nanometre (10-9 metres). ... Grey goo refers to a hypothetical end-of-the-world scenario involving molecular nanotechnology in which out-of-control self-replicating robots consume all living matter on Earth while building more of themselves (a scenario known as ecophagy). ... K. Eric Drexler in 2001. ... Engines of Creation: The Coming Era of Nanotechnology Engines of Creation (ISBN 0-385-19973-2) is a seminal molecular nanotechnology book written by K. Eric Drexler in 1986. ... The Materials Science Tetrahedron, which often also includes Characterization at the center Materials science is an interdisciplinary field involving the properties of matter and its applications to various areas of science and engineering. ... Buckminsterfullerene C60, also known as the buckyball, is the simplest of the carbon structures known as fullerenes. ...

Fundamental concepts

A unique aspect of nanotechnology is the vastly increased ratio of surface area to volume present in many nanoscale materials which opens new possibilities in surface-based science, such as catalysis. A number of physical phenomena become noticeably pronounced as the size of the system decreases. These include statistical mechanical effects, as well as quantum mechanical effects, for example the “quantum size effect” where the electronic properties of solids are altered 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. Additionally, a number of physical properties change when compared to macroscopic systems. One example is the increase in surface area to volume of materials. This catalytic activity also opens potential risks in their interaction with biomaterials. In chemistry and biology, catalysis is the acceleration (increase in rate) of a chemical reaction by means of a substance, called a catalyst, that is itself not consumed by the overall reaction. ... Statistical mechanics is the application of probability theory, which includes mathematical tools for dealing with large populations, to the field of mechanics, which is concerned with the motion of particles or objects when subjected to a force. ... Fig. ... In physics, a quantum (plural: quanta) is an indivisible entity of energy. ... 1) A physical property is an aspect of an object that can be experienced using one of the five human senses: touch, taste, smell, sight or sound, or, in an extended sense, detected through any measuring device. ... In surgery, a biomaterial is a synthetic or natural material used to replace part of a living system or to function in intimate contact with living tissue. ...

Nanotechnology can be thought of as extensions of traditional disciplines towards the explicit consideration of these properties. Additionally, traditional disciplines can be re-interpreted as specific applications of nanotechnology. This dynamic reciprocation of ideas and concepts contributes to the modern understanding of the field. Broadly speaking, nanotechnology is the synthesis and application of ideas from science and engineering towards the understanding and production of novel materials and devices. These products generally make copious use of physical properties associated with small scales.

Materials reduced to the nanoscale can suddenly show very different properties compared to what they exhibit on a macroscale, enabling unique applications. For instance, opaque substances become transparent (copper); inert materials become catalysts (platinum); stable materials turn combustible (aluminum); solids turn into liquids at room temperature (gold); insulators become conductors (silicon). Materials such as gold, which is chemically inert at normal scales, can serve as a potent chemical catalyst at nanoscales. Much of the fascination with nanotechnology stems from these unique quantum and surface phenomena that matter exhibits at the nanoscale. General Name, Symbol, Number gold, Au, 79 Chemical series transition metals Group, Period, Block 11, 6, d Appearance metallic yellow Standard atomic weight 196. ... It has been suggested that this article or section be merged into Catalysis. ...

Nanosize powder particles (a few nanometres in diameter, also called nanoparticles) are potentially important in ceramics, powder metallurgy, the achievement of uniform nanoporosity and similar applications. The strong tendency of small particles to form clumps ("agglomerates") is a serious technological problem that impedes such applications. However, a few dispersants such as ammonium citrate (aqueous) and imidazoline or oleyl alcohol (nonaqueous) are promising additives for deagglomeration. (Dispersants are discussed in "Organic Additives And Ceramic Processing," by Daniel J. Shanefield, Kluwer Academic Publ., Boston.) It has been suggested that nanopowder be merged into this article or section. ... Fixed Partial Denture, or Bridge The word ceramic is derived from the Greek word κεραμικός (keramikos). ... Powder metallurgy is a forming and fabrication technique consisting of three major processing stages. ... Oleyl alcohol is an alcohol coming from inedible beef fat, chemical formula C18H36O. It is an non-ionic, unsaturated fatty alcohol. ... Daniel J. Shanefield is a ceramic engineer. ...

Size concerns

Another concern is that the volume of an object decreases as the third power of its linear dimensions, but the surface area only decreases as its second power. This somewhat subtle and unavoidable principle has huge ramifications. For example the power of a drill (or any other machine) is proportional to the volume, while the friction of the drill's bearings and gears is proportional to their surface area. For a normal-sized drill, the power of the device is enough to handily overcome any friction. However, scaling its length down by a factor of 1000, for example, decreases its power by 1000³ (a factor of a billion) while reducing the friction by only 1000² (a factor of "only" a million). Proportionally it has 1000 times less power per unit friction than the original drill. If the original friction-to-power ratio was, say, 1%, that implies the smaller drill will have 10 times as much friction as power. The drill is useless. The volume of a solid object is the three-dimensional concept of how much space it occupies, often quantified numerically. ... Area is the measure of how much exposed area any two dimensional object has. ... In physics, power (symbol: P) is the rate at which work is performed or energy is transferred. ... A child using an electric drill with a screwdriver bit mounted in the chuck. ... friction is the force that opposes the relative motion or tendency toward such motion of two surfaces in contact. ... A bearing is a device to permit constrained relative motion between two parts, typically rotation or linear movement. ... Spur gears found on a piece of farm equipment A gear is a wheel with teeth around its circumference, the purpose of the teeth being to mesh with similar teeth on another mechanical device -- possibly another gear wheel -- so that force can be transmitted between the two devices in a...

This is why, while super-miniature electronic integrated circuits can be made to function, the same technology cannot be used to make functional mechanical devices in miniature: the friction overtakes the available power at such small scales. So while you may see microphotographs of delicately etched silicon gears, such devices are curiosities with limited real world applications, for example in moving mirrors and shutters. Surface tension increases in the same way, causing very small objects to tend to stick together. This could possibly make any kind of "micro factory" impractical: even if robotic arms and hands could be scaled down, anything they pick up will tend to be impossible to put down. The above being said, molecular evolution has resulted in working cilia, flagella, muscle fibers, and rotary motors in aqueous environments, all on the nanoscale. These machines, however, exploit the increase of the frictional forces found at the micro or nanoscale. Unlike an oar, paddle or propeller the mechanics of which are dominated by normal frictional forces (the frictional forces perpendicular to the surface) for propulsion, cilia, etc., develop motion resulting from the exaggerated drag or laminar forces (frictional forces parallel to the surface) present at micro and nano dimensions. To develop meaningful "machines" at the nanoscale, the relevant forces need to be considered. We are faced with the development and design of relevant machines rather than the simple reproductions of macroscopic ones. Integrated circuit of Atmel Diopsis 740 System on Chip showing memory blocks, logic and input/output pads around the periphery Microchips with a transparent window, showing the integrated circuit inside. ... A molecular assembler is a molecular machine capable of assembling other molecules given instructions, energy, and a supply of smaller building block molecules to work from. ...

All these scaling issues have to be kept in mind while evaluating any kind of nanotechnology.

Materials used in nanotechnology

Materials referred to as "nanomaterials" generally fall into two categories: fullerenes, and inorganic nanoparticles. See also Nanomaterials in List of nanotechnology topics This page aims to list all topics related to the field of nanotechnology. ...

Fullerenes

Buckminsterfullerene C₆₀, also known as the buckyball, is the smallest member of the fullerene family.

Main article: Fullerene

The fullerenes are a class of allotropes of carbon which conceptually are graphene sheets rolled into tubes or spheres. These include the carbon nanotubes which are of interest due to both their mechanical strength and their electrical properties. Image File history File links Download high resolution version (672x623, 147 KB)A 3D model of a C60 molecule, also called a Buckyball. Created by Michael Ströck (mstroeck) on February 6, 2006 in iMol for Mac OS X and Photoshop CS2. ... Image File history File links Download high resolution version (672x623, 147 KB)A 3D model of a C60 molecule, also called a Buckyball. Created by Michael Ströck (mstroeck) on February 6, 2006 in iMol for Mac OS X and Photoshop CS2. ... The Icosahedral Fullerene C540 C60, C-60 and Buckyballs redirect here. ... This article or section does not cite any references or sources. ... It has been suggested that Quasam be merged into this article or section. ... 3D model of three types of single-walled carbon nanotubes. ...

For the past decade, the chemical and physical properties of fullerenes have been a hot topic in the field of research and development, and are likely to continue to be for a long time. In April 2003, fullerenes were under study for potential medicinal use: binding specific antibiotics to the structure to target resistant bacteria and even target certain cancer cells such as melanoma. The October 2005 issue of Chemistry and Biology contains an article describing the use of fullerenes as light-activated antimicrobial agents. In the field of nanotechnology, heat resistance and superconductivity are some of the more heavily studied properties. Nanomedicine is the medical application of nanotechnology. ... Staphylococcus aureus - Antibiotics test plate. ... Phyla/Divisions Actinobacteria Aquificae Bacteroidetes/Chlorobi Chlamydiae/Verrucomicrobia Chloroflexi Chrysiogenetes Cyanobacteria Deferribacteres Deinococcus-Thermus Dictyoglomi Fibrobacteres/Acidobacteria Firmicutes Fusobacteria Gemmatimonadetes Nitrospirae Omnibacteria Planctomycetes Proteobacteria Spirochaetes Thermodesulfobacteria Thermomicrobia Thermotogae Bacteria (singular, bacterium) are a major group of living organisms. ... Cancer is a class of diseases or disorders characterized by uncontrolled division of cells and the ability of these to spread, either by direct growth into adjacent tissue through invasion, or by implantation into distant sites by metastasis (where cancer cells are transported through the bloodstream or lymphatic system). ... Melanoma is a malignant tumor of melanocytes which are found predominantly in skin but also in the bowel and the eye (see uveal melanoma). ... An antimicrobial is a substance that kills or slows the growth of microbes like bacteria (antibacterial activity), fungi (antifungal activity), viruses (antiviral activity), or parasites (antiparasitic activity). ... Buckminsterfullerene C60, also known as the buckyball, is the simplest of the carbon structures known as fullerenes. ... A magnet levitating above a high-temperature superconductor, cooled with liquid nitrogen. ...

A common method used to produce fullerenes is to send a large current between two nearby graphite electrodes in an inert atmosphere. The resulting carbon plasma arc between the electrodes cools into sooty residue from which many fullerenes can be isolated. General Name, Symbol, Number carbon, C, 6 Chemical series nonmetals Group, Period, Block 14, 2, p Appearance black (graphite) colorless (diamond) Standard atomic weight 12. ... A plasma lamp, illustrating some of the more complex phenomena of a plasma, including filamentation. ...

There are many calculations that have been done using ab-initio Quantum Methods applied to fullerenes. By DFT and TDDFT methods one can obtain IR, Raman and UV spectra. Results of such calculations can be compared with experimental results. DFT can have at least four meanings: Discrete Fourier transform Density Functional Theory Design For Test The UKs Department for Transport This is a disambiguation page — a navigational aid which lists other pages that might otherwise share the same title. ... Look up ir in Wiktionary, the free dictionary. ... This article or section does not cite any references or sources. ... Note: Ultraviolet is also the name of a 1998 UK television miniseries about vampires. ...

Nanoparticles

Main article: Nanoparticle

Nanoparticles or nanocrystals made of metals, semiconductors, or oxides are of interest for their electrical, optical, and chemical properties. Nanoparticles have been used as quantum dots and as chemical catalysts. It has been suggested that nanopowder be merged into this article or section. ... A nanocrystal is a crystalline material with dimensions measured in nanometers; a nanoparticle with a structure that is mostly crystalline. ... A quantum dot is a semiconductor nanostructure that confines the motion of conduction band electrons, valence band holes, or excitons (bound pairs of conduction band electrons and valence band holes) in all three spatial directions. ... It has been suggested that this article or section be merged into Catalysis. ...

Nanoparticles are of great scientific interest as they are effectively a bridge between bulk materials and atomic or molecular structures. A bulk material should have constant physical properties regardless of its size, but at the nano-scale this is often not the case. Size-dependent properties are observed such as quantum confinement in semiconductor particles, surface plasmon resonance in some metal particles and superparamagnetism in magnetic materials. The general meaning of atomic is irreducible. That is, reduced to the smallest possible part. ... In science, a molecule is the smallest particle of a pure chemical substance that still retains its chemical composition and properties. ... A potential well is the region surrounding a local minimum of potential energy. ... A semiconductor is a fuckin solid whose electrical conductivity is in between that of a metal and that of an insulator, and can be controlled over a wide range, either permanently or dynamically. ... Surface plasmon resonance, or SPR, is a biophysical technique used by biochemists to measure the binding interactions of very small amounts of a target protein. ... Superparamagnetism refers to materials which become magnetic in the presence of an external magnet, but revert to a non magnetic state when the external magnet is removed. ... In physics, magnetism is a phenomenon by which materials exert an attractive or repulsive force on other materials. ...

Nanoparticles exhibit a number of special properties relative to bulk material. For example, the bending of bulk copper (wire, ribbon, etc.) occurs with movement of copper atoms/clusters at about the 50 nm scale. Copper nanoparticles smaller than 50 nm are considered super hard materials that do not exhibit the same malleability and ductility as bulk copper. The change in properties is not always desirable. Ferroelectric materials smaller than 10 nm can switch their magnetisation direction using room temperature thermal energy, thus making them useless for memory storage. Suspensions of nanoparticles are possible because the interaction of the particle surface with the solvent is strong enough to overcome differences in density, which usually result in a material either sinking or floating in a liquid. Nanoparticles often have unexpected visible properties because they are small enough to confine their electrons and produce quantum effects. For example gold nanoparticles appear deep red to black in solution. General Name, Symbol, Number copper, Cu, 29 Chemical series transition metals Group, Period, Block 11, 4, d Appearance metallic pinkish red Standard atomic weight 63. ... Look up malleability in Wiktionary, the free dictionary. ... Ductility is the physical property of being capable of sustaining large plastic deformations without fracture (in metals, such as being drawn into a wire). ... It has been suggested that this article or section be merged into Mixture. ... A solvent is a liquid that dissolves a solid, liquid, or gaseous solute, resulting in a solution. ... In physics, density is mass m per unit volume V. For the common case of a homogeneous substance, it is expressed as: where, in SI units: ρ (rho) is the density of the substance, measured in kg·m-3 m is the mass of the substance, measured in kg V is... General Name, Symbol, Number gold, Au, 79 Chemical series transition metals Group, Period, Block 11, 6, d Appearance metallic yellow Standard atomic weight 196. ...

Nanoparticles have a very high surface area to volume ratio. This provides a tremendous driving force for diffusion, especially at elevated temperatures. Sintering can take place at lower temperatures, over shorter time scales than for larger particles. This theoretically does not affect the density of the final product, though flow difficulties and the tendency of nanoparticles to agglomerate complicates matters. The surface effects of nanoparticles also reduces the incipient melting temperature. This article does not cite any references or sources. ... This article or section does not cite its references or sources. ... In physics, density is mass m per unit volume V. For the common case of a homogeneous substance, it is expressed as: where, in SI units: ρ (rho) is the density of the substance, measured in kg·m-3 m is the mass of the substance, measured in kg V is... The dissociation of a double-stranded DNA molecule is often referred to as melting because it occurs quickly once a certain temperature has been reached. ...

Safety of Manufactured Nanomaterials

Nanomaterials behave differently than other similarly-sized particles. It is therefore necessary to develop specialized approaches to testing and monitoring their effects on human health and on the environment. The OECD Chemicals Committee has established the Working Party on Manufactured Nanomaterials to address this issue and to study the practices of OECD member countries in regards to nanomaterial safety.^[1]

While nanomaterials and nanotechnologies are expected to yield numerous health and health care advances, such as more targeted methods of delivering drugs, new cancer therapies, and methods of early detection of diseases, they also may have unwanted effects. ^[2] Increased toxicity is the main concern associated with manufactured nanoparticles.

When materials are made into nanoparticles, their reactivity increases. These more reactive particles can enter the body through the skin, lungs, or digestive tract, and may cause inflammation and damage to the lungs as well as other organs. However, the particles must be absorbed in sufficient quantities in order to pose health risks.^[3]

See also

Nanotechnology Buckminsterfullerene C60, also known as the buckyball, is the simplest of the carbon structures known as fullerenes. ...

References

1. ^ “Safety of Manufactured Nanomaterials: About,” OECD Environment Directorate, OECD.org, 18 July 2007 <http://www.oecd.org/about/0,3347,en_2649_37015404_1_1_1_1_1,00.html>.
2. ^ Small Sizes that Matter: Opportunities and Risks of Nanotechnologies, Joint report of the Allianz Center for Technology and the OECD International Futures Programme, ed. Dr. Christoph Lauterwasser, OECD.org 18 July 2007 <http://www.oecd.org/dataoecd/37/19/37770473.pdf> (28).
3. ^ Small Sizes that Matter: Opportunities and Risks of Nanotechnologies, Joint report of the Allianz Center for Technology and the OECD International Futures Programme, ed. Dr. Christoph Lauterwasser, OECD.org 18 July 2007 <http://www.oecd.org/dataoecd/37/19/37770473.pdf> (30-32).

External links

Safety of Manufactured Nanomaterials: OECD Environment Directorate