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57-406: Nanotechnology is the manipulation of matter with at least one dimension sized from 1 to 100 nanometers (nm). At this scale, commonly known as the nanoscale , surface area and quantum mechanical effects become important in describing properties of matter. This definition of nanotechnology includes all types of research and technologies that deal with these special properties. It is common to see

114-406: A meter (0.000000001 m) and to 1000  picometres . One nanometre can be expressed in scientific notation as 1 × 10  m and as ⁠ 1 / 1 000 000 000 ⁠  m. The nanometre was formerly known as the " millimicrometre " – or, more commonly, the " millimicron " for short – since it is ⁠ 1 / 1000 ⁠ of a micrometer . It was often denoted by

171-706: A big-picture view, with more emphasis on societal implications than engineering details. Nanomaterials can be classified in 0D, 1D, 2D and 3D nanomaterials . Dimensionality plays a major role in determining the characteristic of nanomaterials including physical , chemical , and biological characteristics. With the decrease in dimensionality, an increase in surface-to-volume ratio is observed. This indicates that smaller dimensional nanomaterials have higher surface area compared to 3D nanomaterials. Two dimensional (2D) nanomaterials have been extensively investigated for electronic , biomedical , drug delivery and biosensor applications. The atomic force microscope (AFM) and

228-447: A chemically inert substance that was geometrically closed with no dangling bonds . Curl was responsible for determining the optimal conditions of the carbon vapor in the apparatus, and examining the spectrograph. Curl noted that James R. Heath and Sean C. O'Brien deserve equal recognition in the work to Smalley and Kroto. The existence of this type of molecule had earlier been theorized by others, but Curl and his colleagues were at

285-488: A debate among advocacy groups and governments on whether special regulation of nanotechnology is warranted. The concepts that seeded nanotechnology were first discussed in 1959 by physicist Richard Feynman in his talk There's Plenty of Room at the Bottom , in which he described the possibility of synthesis via direct manipulation of atoms. The term "nano-technology" was first used by Norio Taniguchi in 1974, though it

342-437: A field in the 1980s occurred through the convergence of Drexler's theoretical and public work, which developed and popularized a conceptual framework, and high-visibility experimental advances that drew additional attention to the prospects. In the 1980s, two breakthroughs sparked the growth of nanotechnology. First, the invention of the scanning tunneling microscope in 1981 enabled visualization of individual atoms and bonds, and

399-725: A fuel catalyst. In the electric car industry, single wall carbon nanotubes (SWCNTs) address key lithium-ion battery challenges, including energy density, charge rate, service life, and cost. SWCNTs connect electrode particles during charge/discharge process, preventing battery premature degradation. Their exceptional ability to wrap active material particles enhanced electrical conductivity and physical properties, setting them apart multi-walled carbon nanotubes and carbon black. Further applications allow tennis balls to last longer, golf balls to fly straighter, and bowling balls to become more durable. Trousers and socks have been infused with nanotechnology to last longer and lower temperature in

456-433: A larger scale and come under the description of microtechnology . To put that scale in another context, the comparative size of a nanometer to a meter is the same as that of a marble to the size of the earth. Two main approaches are used in nanotechnology. In the "bottom-up" approach, materials and devices are built from molecular components which assemble themselves chemically by principles of molecular recognition . In

513-470: A manufacturing technology based on the mechanical functionality of these components (such as gears, bearings, motors, and structural members) that would enable programmable, positional assembly to atomic specification. The physics and engineering performance of exemplar designs were analyzed in Drexler's book Nanosystems: Molecular Machinery, Manufacturing, and Computation . In general, assembling devices on

570-519: A nine-year-old, recalling that he ruined the finish on his mother's porcelain stove when nitric acid boiled over onto it. He is a graduate of Thomas Jefferson High School in San Antonio, Texas . His high school offered only one year of chemistry instruction, but in his senior year his chemistry teacher gave him special projects to work on. Curl received a Bachelor of Arts in chemistry from Rice Institute (now Rice University) in 1954. He

627-761: A protein . Thus, components can be designed to be complementary and mutually attractive so that they make a more complex and useful whole. Such bottom-up approaches should be capable of producing devices in parallel and be much cheaper than top-down methods, but could potentially be overwhelmed as the size and complexity of the desired assembly increases. Most useful structures require complex and thermodynamically unlikely arrangements of atoms. Nevertheless, many examples of self-assembly based on molecular recognition in exist in biology , most notably Watson–Crick basepairing and enzyme-substrate interactions. Molecular nanotechnology, sometimes called molecular manufacturing, concerns engineered nanosystems (nanoscale machines) operating on

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684-670: A public debate between Drexler and Smalley in 2001 and 2003. Meanwhile, commercial products based on advancements in nanoscale technologies began emerging. These products were limited to bulk applications of nanomaterials and did not involve atomic control of matter. Some examples include the Silver Nano platform for using silver nanoparticles as an antibacterial agent, nanoparticle -based sunscreens, carbon fiber strengthening using silica nanoparticles, and carbon nanotubes for stain-resistant textiles. Governments moved to promote and fund research into nanotechnology, such as American

741-447: A scale of nanometres (see nanoscopic scale ). The nanometre is often used to express dimensions on an atomic scale: the diameter of a helium atom, for example, is about 0.06 nm, and that of a ribosome is about 20 nm. The nanometre is also commonly used to specify the wavelength of electromagnetic radiation near the visible part of the spectrum : visible light ranges from around 400 to 700 nm. The ångström , which

798-980: A surface with scanning probe microscopy techniques. Various techniques of lithography, such as optical lithography , X-ray lithography , dip pen lithography, electron beam lithography or nanoimprint lithography offer top-down fabrication techniques where a bulk material is reduced to a nano-scale pattern. Another group of nano-technological techniques include those used for fabrication of nanotubes and nanowires , those used in semiconductor fabrication such as deep ultraviolet lithography, electron beam lithography, focused ion beam machining, nanoimprint lithography, atomic layer deposition , and molecular vapor deposition , and further including molecular self-assembly techniques such as those employing di-block copolymers . In contrast, bottom-up techniques build or grow larger structures atom by atom or molecule by molecule. These techniques include chemical synthesis, self-assembly and positional assembly. Dual-polarization interferometry

855-401: A useful conformation through a bottom-up approach. The concept of molecular recognition is important: molecules can be designed so that a specific configuration or arrangement is favored due to non-covalent intermolecular forces . The Watson–Crick basepairing rules are a direct result of this, as is the specificity of an enzyme targeting a single substrate , or the specific folding of

912-463: A wide variety of useful chemicals such as pharmaceuticals or commercial polymers . This ability raises the question of extending this kind of control to the next-larger level, seeking methods to assemble single molecules into supramolecular assemblies consisting of many molecules arranged in a well-defined manner. These approaches utilize the concepts of molecular self-assembly and/or supramolecular chemistry to automatically arrange themselves into

969-1055: Is controlled via changing voltage: a nanotube nanomotor , a molecular actuator, and a nanoelectromechanical relaxation oscillator. Ho and Lee at Cornell University in 1999 used a scanning tunneling microscope to move an individual carbon monoxide molecule (CO) to an individual iron atom (Fe) sitting on a flat silver crystal and chemically bound the CO to the Fe by applying a voltage. Many areas of science develop or study materials having unique properties arising from their nanoscale dimensions. The bottom-up approach seeks to arrange smaller components into more complex assemblies. These seek to create smaller devices by using larger ones to direct their assembly. Functional approaches seek to develop useful components without regard to how they might be assembled. These subfields seek to anticipate what inventions nanotechnology might yield, or attempt to propose an agenda along which inquiry could progress. These often take

1026-516: Is equal to 0.1 nm, was formerly used for these purposes. Since the late 1980s, in usages such as the 32 nm and the 22 nm semiconductor node , it has also been used to describe typical feature sizes in successive generations of the ITRS Roadmap for miniaturized semiconductor device fabrication in the semiconductor industry . The CJK Compatibility block in Unicode has

1083-449: Is known in the residential college life at Rice University for being the first master of Lovett College . Curl retired in 2008 at the age of 74, becoming a University Professor Emeritus , Pitzer-Schlumberger Professor of Natural Sciences Emeritus, and Professor of Chemistry Emeritus at Rice University. Curl married Jonel Whipple in 1955, with whom he had two children. He cycled to his office and lab and every week played bridge with

1140-434: Is one tool suitable for characterization of self-assembled thin films. Another variation of the bottom-up approach is molecular-beam epitaxy or MBE. Researchers at Bell Telephone Laboratories including John R. Arthur . Alfred Y. Cho , and Art C. Gossard developed and implemented MBE as a research tool in the late 1960s and 1970s. Samples made by MBE were key to the discovery of the fractional quantum Hall effect for which

1197-663: Is still a slow process because of low velocity of the microscope. The top-down approach anticipates nanodevices that must be built piece by piece in stages, much as manufactured items are made. Scanning probe microscopy is an important technique both for characterization and synthesis. Atomic force microscopes and scanning tunneling microscopes can be used to look at surfaces and to move atoms around. By designing different tips for these microscopes, they can be used for carving out structures on surfaces and to help guide self-assembling structures. By using, for example, feature-oriented scanning approach, atoms or molecules can be moved around on

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1254-402: Is the science and engineering of functional systems at the molecular scale. In its original sense, nanotechnology refers to the projected ability to construct items from the bottom up making complete, high-performance products. One nanometer (nm) is one billionth, or 10, of a meter. By comparison, typical carbon–carbon bond lengths , or the spacing between these atoms in a molecule , are in

1311-545: The 1998 Nobel Prize in Physics was awarded. MBE lays down atomically precise layers of atoms and, in the process, build up complex structures. Important for research on semiconductors, MBE is also widely used to make samples and devices for the newly emerging field of spintronics . Therapeutic products based on responsive nanomaterials , such as the highly deformable, stress-sensitive Transfersome vesicles, are approved for human use in some countries. As of August 21, 2008,

1368-641: The National Institute for Occupational Safety and Health research potential health effects stemming from exposures to nanoparticles. Nanometers The nanometre (international spelling as used by the International Bureau of Weights and Measures ; SI symbol: nm ), or nanometer ( American spelling ), is a unit of length in the International System of Units (SI), equal to one billionth ( short scale ) of

1425-689: The National Nanotechnology Initiative , which formalized a size-based definition of nanotechnology and established research funding, and in Europe via the European Framework Programmes for Research and Technological Development . By the mid-2000s scientific attention began to flourish. Nanotechnology roadmaps centered on atomically precise manipulation of matter and discussed existing and projected capabilities, goals, and applications. Nanotechnology

1482-653: The Project on Emerging Nanotechnologies estimated that over 800 manufacturer-identified nanotech products were publicly available, with new ones hitting the market at a pace of 3–4 per week. Most applications are "first generation" passive nanomaterials that includes titanium dioxide in sunscreen, cosmetics, surface coatings, and some food products; Carbon allotropes used to produce gecko tape ; silver in food packaging , clothing, disinfectants, and household appliances; zinc oxide in sunscreens and cosmetics, surface coatings, paints and outdoor furniture varnishes; and cerium oxide as

1539-577: The Scanning Tunneling Microscope (STM) are two versions of scanning probes that are used for nano-scale observation. Other types of scanning probe microscopy have much higher resolution, since they are not limited by the wavelengths of sound or light. The tip of a scanning probe can also be used to manipulate nanostructures (positional assembly). Feature-oriented scanning may be a promising way to implement these nano-scale manipulations via an automatic algorithm . However, this

1596-520: The Technion in order to increase youth interest in nanotechnology. One concern is the effect that industrial-scale manufacturing and use of nanomaterials will have on human health and the environment, as suggested by nanotoxicology research. For these reasons, some groups advocate that nanotechnology be regulated. However, regulation might stifle scientific research and the development of beneficial innovations. Public health research agencies, such as

1653-591: The University of Sussex . Born in Alice, Texas , United States, Curl was the son of a Methodist minister . Due to his father's missionary work, his family moved several times within southern and southwestern Texas, and the elder Curl was involved in starting the San Antonio Medical Center's Methodist Hospital. Curl attributes his interest in chemistry to a chemistry set he received as

1710-422: The bond angle of disiloxane . Curl was a postdoctoral fellow at Harvard University with E. B. Wilson , where he used microwave spectroscopy to study the bond rotation barriers of molecules. After that, he joined the faculty of Rice University in 1958. He inherited the equipment and graduate students of George Bird , a professor who was leaving for a job at Polaroid . Curl's early research involved

1767-788: The " quantum size effect" in which the electronic properties of solids alter along with reductions in particle size. Such effects do not apply at macro or micro dimensions. However, quantum effects can become significant when nanometer scales. Additionally, physical (mechanical, electrical, optical, etc.) properties change versus macroscopic systems. One example is the increase in surface area to volume ratio altering mechanical, thermal, and catalytic properties of materials. Diffusion and reactions can be different as well. Systems with fast ion transport are referred to as nanoionics. The mechanical properties of nanosystems are of interest in research. Modern synthetic chemistry can prepare small molecules of almost any structure. These methods are used to manufacture

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1824-420: The "top-down" approach, nano-objects are constructed from larger entities without atomic-level control. Areas of physics such as nanoelectronics , nanomechanics , nanophotonics and nanoionics have evolved to provide nanotechnology's scientific foundation. Several phenomena become pronounced as system size. These include statistical mechanical effects, as well as quantum mechanical effects, for example,

1881-468: The 1996 Nobel Prize in Chemistry . C 60 was not initially described as nanotechnology; the term was used regarding subsequent work with related carbon nanotubes (sometimes called graphene tubes or Bucky tubes) which suggested potential applications for nanoscale electronics and devices. The discovery of carbon nanotubes is largely attributed to Sumio Iijima of NEC in 1991, for which Iijima won

1938-492: The Nobel Prize in 1996, Curl took a quieter path than Smalley, who became an outspoken advocate of nanotechnology, and Kroto, who used his fame to further his interest in science education, saying, "After winning a Nobel, you can either become a scientific pontificator, or you can have some idea for a new science project and you can use your newfound notoriety to get the resources to do it. Or you can say, 'Well, I enjoy what I

1995-776: The atomic scale requires positioning atoms on other atoms of comparable size and stickiness. Carlo Montemagno 's view is that future nanosystems will be hybrids of silicon technology and biological molecular machines. Richard Smalley argued that mechanosynthesis was impossible due to difficulties in mechanically manipulating individual molecules. This led to an exchange of letters in the ACS publication Chemical & Engineering News in 2003. Though biology clearly demonstrates that molecular machines are possible, non-biological molecular machines remained in their infancy. Alex Zettl and colleagues at Lawrence Berkeley Laboratories and UC Berkeley constructed at least three molecular devices whose motion

2052-421: The doctors' offices and at homes. Cars use nanomaterials in such ways that car parts require fewer metals during manufacturing and less fuel to operate in the future. Nanoencapsulation involves the enclosure of active substances within carriers. Typically, these carriers offer advantages, such as enhanced bioavailability, controlled release, targeted delivery, and protection of the encapsulated substances. In

2109-657: The fields of infrared and microwave spectroscopy. Curl's research inspired Richard Smalley to come to Rice in 1976 with the intention of collaborating with Curl. In 1985, Curl was contacted by Harold Kroto, who wanted to use a laser beam apparatus built by Smalley to simulate and study the formation of carbon chains in red giant stars. Smalley and Curl had previously used this apparatus to study semiconductors such as silicon and germanium . They were initially reluctant to interrupt their experiments on these semiconductor materials to use their apparatus for Kroto's experiments on carbon, but eventually gave in. They indeed found

2166-609: The inaugural 2008 Kavli Prize in Nanoscience. In the early 2000s, the field garnered increased scientific, political, and commercial attention that led to both controversy and progress. Controversies emerged regarding the definitions and potential implications of nanotechnologies, exemplified by the Royal Society 's report on nanotechnology. Challenges were raised regarding the feasibility of applications envisioned by advocates of molecular nanotechnology, which culminated in

2223-427: The long carbon chains they were looking for, but also found an unexpected product that had 60 carbon atoms. Over the course of 11 days, the team studied and determined its structure and named it buckminsterfullerene after noting its similarity to the geodesic domes for which the architect Buckminster Fuller was known. This discovery was based solely on the single prominent peak on the mass spectrograph , implying

2280-607: The medical field, nanoencapsulation plays a significant role in drug delivery . It facilitates more efficient drug administration, reduces side effects, and increases treatment effectiveness. Nanoencapsulation is particularly useful for improving the bioavailability of poorly water-soluble drugs, enabling controlled and sustained drug release, and supporting the development of targeted therapies. These features collectively contribute to advancements in medical treatments and patient care. Nanotechnology may play role in tissue engineering . When designing scaffolds, researchers attempt to mimic

2337-439: The microwave spectroscopy of chlorine dioxide . His research program included both experiment and theory, mainly focused on detection and analysis of free radicals using microwave spectroscopy and tunable lasers. He used these observations to develop the theory of their fine structure and hyperfine structure , as well as information about their structure and the kinetics of their reactions. Curl's research at Rice involved

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2394-443: The molecular scale. Molecular nanotechnology is especially associated with molecular assemblers , machines that can produce a desired structure or device atom-by-atom using the principles of mechanosynthesis . Manufacturing in the context of productive nanosystems is not related to conventional technologies used to manufacture nanomaterials such as carbon nanotubes and nanoparticles. When Drexler independently coined and popularized

2451-402: The nanoscale features of a cell 's microenvironment to direct its differentiation down a suitable lineage. For example, when creating scaffolds to support bone growth, researchers may mimic osteoclast resorption pits. Researchers used DNA origami -based nanobots capable of carrying out logic functions to target drug delivery in cockroaches. A nano bible (a .5mm2 silicon chip) was created by

2508-500: The nanoscale to direct control of matter on the atomic scale . Nanotechnology may be able to create new materials and devices with diverse applications , such as in nanomedicine , nanoelectronics , biomaterials energy production, and consumer products. However, nanotechnology raises issues, including concerns about the toxicity and environmental impact of nanomaterials, and their potential effects on global economics, as well as various doomsday scenarios . These concerns have led to

2565-770: The plural form "nanotechnologies" as well as "nanoscale technologies" to refer to research and applications whose common trait is scale. An earlier understanding of nanotechnology referred to the particular technological goal of precisely manipulating atoms and molecules for fabricating macroscale products, now referred to as molecular nanotechnology . Nanotechnology defined by scale includes fields of science such as surface science , organic chemistry , molecular biology , semiconductor physics , energy storage , engineering , microfabrication , and molecular engineering . The associated research and applications range from extensions of conventional device physics to molecular self-assembly , from developing new materials with dimensions on

2622-516: The range 0.12–0.15 nm , and DNA 's diameter is around 2 nm. On the other hand, the smallest cellular life forms, the bacteria of the genus Mycoplasma , are around 200 nm in length. By convention, nanotechnology is taken as the scale range 1 to 100 nm , following the definition used by the American National Nanotechnology Initiative . The lower limit is set by the size of atoms (hydrogen has

2679-406: The smallest atoms, which have an approximately ,25 nm kinetic diameter ). The upper limit is more or less arbitrary, but is around the size below which phenomena not observed in larger structures start to become apparent and can be made use of. These phenomena make nanotechnology distinct from devices that are merely miniaturized versions of an equivalent macroscopic device; such devices are on

2736-487: The summer. Bandages are infused with silver nanoparticles to heal cuts faster. Video game consoles and personal computers may become cheaper, faster, and contain more memory thanks to nanotechnology. Also, to build structures for on chip computing with light, for example on chip optical quantum information processing, and picosecond transmission of information. Nanotechnology may have the ability to make existing medical applications cheaper and easier to use in places like

2793-561: The symbol U+339A ㎚ SQUARE NM . Robert Curl Robert Floyd Curl Jr. (August 23, 1933 – July 3, 2022) was an American chemist who was Pitzer–Schlumberger Professor of Natural Sciences and professor of chemistry at Rice University . He was awarded the Nobel Prize in Chemistry in 1996 for the discovery of the nanomaterial buckminsterfullerene , and hence the fullerene class of materials, along with Richard Smalley (also of Rice University) and Harold Kroto of

2850-547: The symbol mμ or, more rarely, as μμ (however, μμ should refer to a millionth of a micron). The name combines the SI prefix nano- (from the Ancient Greek νάνος , nanos , "dwarf") with the parent unit name metre (from Greek μέτρον , [metrοn] Error: {{Lang}}: Non-latn text/Latn script subtag mismatch ( help ) , "unit of measurement"). Nanotechnologies are based on physical processes which occur on

2907-486: The term "nanotechnology", he envisioned manufacturing technology based on molecular machine systems. The premise was that molecular-scale biological analogies of traditional machine components demonstrated molecular machines were possible: biology was full of examples of sophisticated, stochastically optimized biological machines . Drexler and other researchers have proposed that advanced nanotechnology ultimately could be based on mechanical engineering principles, namely,

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2964-555: The time unaware of this. Later experiments confirmed their proposed structure, and the team moved on to synthesize endohedral fullerenes that had a metal atom inside the hollow carbon shell. The fullerenes , a class of molecules of which buckminsterfullerene was the first member discovered, are now considered to have potential applications in nanomaterials and molecular scale electronics . Robert Curl's 1985 paper entitled "C60: Buckminsterfullerine", published with colleagues H. Kroto, J. R. Heath, S. C. O’Brien, and R. E. Smalley,

3021-467: Was attracted to the reputation of both the school's academics and football team, and the fact that at the time it charged no tuition. He earned his doctorate in chemistry from the University of California, Berkeley , in 1957. At Berkeley, he worked in the laboratory of Kenneth Pitzer , then dean of the college of chemistry, with whom he would become a lifelong collaborator. Curl's graduate research involved performing infrared spectroscopy to determine

3078-561: Was doing, and I want to keep doing that.'" True to that humility, when asked by the President of Rice what he would like, following the Nobel announcement, he asked that a bike rack be installed closer to his office and laboratory. Curl's later research interests involved physical chemistry , developing DNA genotyping and sequencing instrumentation, and creating photoacoustic sensors for trace gases using quantum cascade lasers . He

3135-772: Was honored by a Citation for Chemical Breakthrough Award from the Division of History of Chemistry of the American Chemical Society, presented to Rice University in 2015. The discovery of fullerenes was recognized in 2010 by the designation of a National Historic Chemical Landmark by the American Chemical Society at the Richard E. Smalley Institute for Nanoscale Science and Technology at Rice University in Houston, Texas. After winning

3192-530: Was not widely known. Inspired by Feynman's concepts, K. Eric Drexler used the term "nanotechnology" in his 1986 book Engines of Creation: The Coming Era of Nanotechnology , which proposed the idea of a nanoscale "assembler" that would be able to build a copy of itself and of other items of arbitrary complexity with atom-level control. Also in 1986, Drexler co-founded The Foresight Institute to increase public awareness and understanding of nanotechnology concepts and implications. The emergence of nanotechnology as

3249-431: Was successfully used to manipulate individual atoms in 1989. The microscope's developers Gerd Binnig and Heinrich Rohrer at IBM Zurich Research Laboratory received a Nobel Prize in Physics in 1986. Binnig, Quate and Gerber also invented the analogous atomic force microscope that year. Second, fullerenes (buckyballs) were discovered in 1985 by Harry Kroto , Richard Smalley , and Robert Curl , who together won

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