A detailed study on Nano Technology

The word ‘atom’ coined by Democritus as early as 400 B.C to denote the smallest particle ‘not cleavable’ any further engaging the whole world in its physical, chemical and natural phenomenon. Originally, coined by K. Eric Drexler, in ‘Engine of Creation’ the term “NANOTECHNOLOGY” (nanotech) is used to describe an interdisciplinary field where in the critical dimensions of material, devices and system are in nanometer (10^-9)scale. Noria Taniguchi used the term nanotech while measuring precise machining tolerances & made it stuck to all tiny technologies from material science and metallurgy.

The most common definition of nanotechnology is that of manipulation, observation and measurement at a scale of less than 100 nanometers (one nanometer is one millionth of a millimeter). However, the emergence of a multi-disciplinary field called nanotechnology’ arises from new instrumentation only recently available, and a flow of public money into a great number of techniques and relevant academic disciplines in what has been described as an ‘arms race’ between governments. Nanotechnology is really a convenient label for a variety of scientific disciplines which serves as a way of getting money from Government budgets Three new business alliances have recently been formed in the US, Europe and Asia, whose sole purpose is to translate research into economically viable products.

There is now a great deal of momentum behind nanotechnology that has built up into a force which might already struggle to incorporate the outcomes of organized public debate, or meet well-founded public concerns, although by no means will all of the developments be controversial – many will not. Nanotechnology involves research and development at the atomic, molecular, or macromolecular levels to create and use structures, devices, and systems that have novel functional properties because of their size. Positioned as it is where engineering, biotechnology, medicine, physical sciences, and information technology meet, nanotechnology is spurring new directions in research, education, and technology transfer. Nanotechnology involves research and development at the atomic, molecular, or macromolecular levels to create and use structures, devices, and systems that have novel functional properties because of their size. Positioned as it is where engineering, biotechnology, medicine, physical sciences, and information
technology meet, nanotechnology is spurring new directions in research, education, and technology transfer.

INTRODUCTION - About nanotechnology

There are a number of ways in which nanotechnology may be defined. The most common version regards nanoscience as ‘the ability to do things – measure, see, predict and make – on the scale of atoms and molecules and exploit the novel properties found at that scale’.

Traditionally, this scale is defined as being between 0.1 and 100 nanometers (nm), 1 nm being one-thousandth of a micron (micrometer; mm), which is, in turn, one-thousandth of a millimeter (mm). However, as will become clear in the later stages of this study, this definition is open to interpretation, and may readily be applied to a number of different technologies that have no obvious common relationship. Another way to characterize nanotechnology is by distinguishing between the fabrications processes of top-down and bottom-up. Top–down technology refers to the ‘fabrication of nanoscale structures by machining and etching techniques’. However, top-down means more than just miniaturizations: at the nanoscale level different laws of physics come into play, properties of traditional materials change, and the behaviors of surfaces start to dominate the behaviors of bulk materials. On the other hand, bottom-up technology often referred to as molecular nanotechnology – applies to the creation of organic and inorganic structures, atom by atom, or molecule by molecule. It is this area of nanotechnology that has created the most excitement and publicity. In a mature nanotech world, macrostructures would simply be grown from their smallest constituent components: an ‘anything box’ would take a molecular seed containing instructions for building a product and use tiny nanobots or molecular machines to build it atom by atom. As it is said that, ‘the development of technology does not depend upon on discovering new scientific principles. The advances required are engineering.’ In short, fully-fledged bottom-up anotechnology promises nothing less than complete control over the physical structure of matter.

Present Situation

At present it is clear that this bottom-up ‘dream’ is far from being realized. ‘Top-down and bottom-up can be a measure of the level of advancement of nanotechnology, and nanotechnology, as applied today, is still mainly in the top-down stage.’ This state of relative infancy is often compared in the literature to the information technology sector in the 1960s, or biotechnology in the 1980s. So, with the science fiction aspects of the debate rapidly receding, industry has now necessarily adopted much more realistic expectations. This is not to say, however, that we have long to wait before nanotechnology make its mark in the global market. In fact, current industry jargon would probably describe nanotechnology as ‘coming on stream’. For, although the underlying technologies and their applications are still at an early stage of development, there are applications emerging into the market that are likely to be making a significant impact on the industrial scene by 2006.

Science of the ‘small’

One nanometer (nm) is one billionth of a meters or around 80,000 times smaller than the width of a human hair. Nanotechnology is generally considered to cover the range where dimensions and tolerances from sub-nanometre the size of a single water molecule to100 nm play a critical role. The scientific and technical challenges of working at this scale are huge.

RESEARCH AND DEVELOPMENTS

The absence of a universally accepted strict definition of nanotechnology has allowed there search emphasis to broaden, encompassing many areas of work that have traditionally been referred to as chemistry or biology. Thus, the first major characteristic of activity grouped under this section is that contemporary R&D cuts across a wide range of industrial sectors. In some cases, major markets are fairly well defined. The food industry serves as a good example here, where there are significant drivers at work. To illustrate, ‘smart’ wrappings for the food industry (that indicate freshness or otherwise) are close to the market By 2006, beer packaging is anticipated by industry to use the highest weight of nano-strengthened material, at 3 million lbs., followed by meats and carbonated soft drinks. By 2011, meanwhile, the total figure might reach almost 100 million lbs.

In other cases, important applications are identified but the eventual market impacts are more difficult to predict. For example, nanotechnology is anticipated to yield significant advances in catalyst technology. If these potential applications are realized then the impact on society will be dramatic as catalysts, arguably the most important technology in our modern society, enable the production of a wide range of materials and fuels.

Novel Materials

The major characteristic of activity grouped under this section concerns that fact that nanotechnology is primarily about making things. And for this reason, most of the existing focus of R&D centers on ‘nano materials’: novel materials whose molecular structure has been engineered at the nanometre scale. Indeed, it is stated that: ‘material science and technology is fundamental to a majority of the applications of nanotechnology.’ Thus, many of the materials that follow involve either bulk production of conventional compounds that are much smaller (and hence exhibit different properties) or new nanomaterials, such as fullerenes and nanotubes. The markets ranges of nonmaterial are considerable. Indeed, it has been estimated that, aided by nanotechnology, novel materials and processes can be expected to have a market impact of over US$340 billion within a decade.

Figure:-Novel materials, made by coaxing nanoparticles to assemble themselves into three-dimensional patterns, offer intriguing magnetic and optical properties

Nanotubes

The term nanotube is normally used to refer to the carbon nanotube, which has received enormous attention from researchers over the last few years and promises, along with close relatives such as the nanohorn, a host of interesting applications. There are many other types of nanotube, from various inorganic kinds, such as those made from boron nitride, to organic ones, such as those made from self-assembling cyclic peptides (protein components) or from naturally-occurring heat shock proteins (extracted from bacteria that thrive in extreme environments). However, carbon nanotubes excite the most interest, promise the greatest variety of applications, and currently appear to have by far the highest commercial potential. They are in fact a hugely varied range of structures, with similarly huge variations in properties and ease of production. Adding to the confusion is the existence of long, thin, and often hollow, carbon fibers that have been called carbon nanotubes but have a quite different make-up from that of the nanotubes that scientists generally refer to.

One of the major classifications of carbon nanotubes is into single-walled varieties, which have a single cylindrical wall, and multi-walled varieties, which have cylinders within cylinders.

Nanotubes provide a good example of how basic R&D can take off into full-scale market application in one specific area. Described as ‘the most important material in nanotechnology today’, nanotubes are a new material with remarkable tensile strength. Indeed, taking current technical barriers into account, nanotube-based material is anticipated to become 50–100 times stronger than steel at one-sixth of the weight. This development would dwarf the improvements that carbon fibers brought to composites. The nanotube may be the key to overcoming this longstanding obstacle, making the space elevator a reality in just 15 years time.

Nanotubes Applications

• Many applications are envisaged

• Space and aircraft manufacture

• Automobiles and construction.

• Multi-layered carbon nanotubes.

National Funding For Research and Developments

The main reason for government interest in nanotechnology is strategic: to achieve an advantageous position so that when nanotech applications begin to have a significant effect in the world economy, countries are able to exploit these new opportunities to the full. Levels of public investment in nanotechnology are reminiscent of a growing strategic interest: this is an area that attracts both large and small countries. Global R&D spending is currently around US$4 billion, with public investment increasing rapidly.
Table: World-wide government funding for nanotechnology research and developments (US million).

Figure:-National Spending On Nanotechnology

BENEFITS OF NANOTECHNOLOGY

MOLECULAR NANOTECHNOLOGY (MNT) manufacturing can solve many of the world’s current problems. For example simple products like pipes, filters, and mosquito nets can greatly reduce the of water problem. Information and communication are valuable, but lacking in many places. Computers and display devices would become stunningly cheap. Electrical power is still not available in many areas. The efficient, cheap building of light, strong structures, electrical equipment, and power storage devices would allow the use of solar thermal power as a primary and abundant energy source.

Environmental degradation is a serious problem worldwide. High-tech products can allow people to live with much less environmental impact. Many areas of the world cannot rapidly bootstrap a 20th century manufacturing infrastructure. Molecular manufacturing can be self-contained and clean; a single packing crate or suitcase could contain all equipment required for a village-scale industrial revolution. Finally, MNT will provide cheap and advanced equipment for medical research and health care, making improved medicine widely available. Much social unrest can be traced directly to material poverty, ill health, and ignorance. MNT can contribute to great reductions in all of these problems, and in the associated human suffering.

Nanotechnology is expected to touch almost every aspect of our lives, right down to the water we drink and the air we breathe. Once we have the ability to capture, position, and change the configuration of a molecule, we should be able to create filtration systems that will scrub the toxins from the air or remove hazardous organisms from the water we drink. We should be able to begin the long process of cleaning up our environment.
Space will also open up to us in new ways. With the current cost of transporting payloads into space being so high (-$20,000/kg), little is being done to take advantage of space. Nanotechnology will help by allowing us to deliver more machines of smaller size and greater functionality into space, paving the way for solar system expansion. Some have suggested that application of medical nanotechnology might even go so far as to allow us to adapt our bodies for survival in space or on other worlds.

Taking all of this into account it is clear that nanotechnology should improve our lives in any area that would benefit from the development of better faster, stronger, smaller and cheaper systems.

APPLICATIONS
- Electronic nanocomponents. (Diodes, Transistors, Nano-wires, etc. )

- Field Emission.

- Multi-Functional Composites.

- EMI Shielding, Thermal Conducting, Strengthen, Conducting, etc

- Hydrogen storage.

- Rechargeable lithium batteries.

- Atomic Force Microscope (AFM) tips.

- Electrode material of super capacitors.

- Biosensors.

- Pharmaceuticals & Medicines

- Electricity Generation.

-Military Applications

- Agricultural purpose

RESULT

Thus, top down approach on which researches are been conducted in the laboratories of world by various chemists and physicists, engineers and biologists all together has started solving the puzzles and challenges faced by the nanotech i.e. tailoring the physicochemical and optoelectronic properties of nanoparticle and their size and shape control for worldwide applications by synthesizing powdered and amorphous forms of nanoparticles though on small scale due to its cost limitations.

CONCLUSION

Nanotech industry is heralding the new world. It is heavily interwined with biotechnology and information technology, making its scope very wide. It as a scientific thrust encompasses best of opportunities by scientific, industrial and engineering communities.
Only word of caution associated with this bright frontier is that decisions must be based on sound scientific merit having experimental evidence or valid theoretical foundation combined with a realistic assessment of challenges that must be met to fulfill the promise.