Nanotechnology Application
May 13, 2009 – 11:31 am
‘Nanotechnology is about making things, whether it be making things that are smaller,
faster, or stronger, making something completely new or with additional properties, or
making machines that will lead to new manufacturing paradigms’ [1].
Three factors define nanotechnolgy: small size, new properties, and the integration of the technology in to materials and devices. Nanotechnology covers a broad range of science, drawing concepts, knowledge and expertise, skills, and materials from all the three classical sciences, physics, chemistry, and biology.
From an economic point of view the potential of nanotechnology is clearly vast, with the
drive to be smaller, faster, lower power and cheaper. As size is reduced, overheads
(materials, energy, factory and manpower requirements) are all reduced.
Recent nanotechnology products poised for near-term market realization include a
molecule-sized electronic switch, improved sun cream, and a fullerene-based cancer
treatment. In medicine nanoceramics are currently being used as bone replacement agents. These ceramics show outstanding osteoblast (cells that form bone) proliferation and mechanical properties [2].
One obvious area where nanotechnology has vast potential is in computing, in particular the ever-shrinking computer chip. 1965 saw the birth of Moore’s law, named after Gordon Moore of Intel, who stated that the number of transistors per integrated circuit would double every 18 months [3]. Turning this on its head, the size of chips would half every 18 months. This has held true since 1965, but now, with chip sizes expected to approach the atomistic scale in the next decade or so, the need for nanotechnology to shrink the chips ever more is clearly obvious with atom-scaled circuits required.
And, of course, atom-scaled chips would go in atom-scaled computers, constructed and assembled by other atom-scaled devices. IBM is currently undertaking pioneering work in this respect with a quantum mirage of cobalt atoms forming a potential data transfer tool. HP recently reported fabrication of nanoscale molecular-electronic devices comprising a single molecular monolayer of bistable rotaxanes sandwiched between two 40-nm metal electrodes [4].
So where now for this exciting science? How to go about the exploration of the vast range of scientific and technological opportunities offered by the advances of controlling
materials at the nanoscale? Challenges the researcher is faced with include the selection and screening of potentially large libraries of molecules and materials, the fact that ‘almost any’ molecule can be synthesized but synthesis can still be very costly, and the unambiguous interpretation of experimental information at the nanoscale level, where quantum effects are often important.
Today’s computing power is proving invaluable in the research behind the miniaturization. Computer molecular modeling and simulation is being used in the drive to advance this exciting and cutting edge scientific field, enabling scientists to visualize and predict behavior at the nanoscale. And with the major cost vs. performance barrier being blown away by today’s rapid computing developments, these techniques are set to become widespread throughout all research and development, not just in nanotechnology.
Computational tools enable scientists to simulate reactions and study the properties and
interactions of molecules and materials at a computer interface. Once the preserve of
computer experts, the widespread availability and use of personal computers, coupled with the almost exponential increase in available hardware power, has resulted in these
techniques becoming a widespread research tool, resulting in many advantages.
The tools can be used to complement, direct, and refine and, in some cases, even replace experimentation. The need to use ‘real’ chemicals can be reduced, not only saving resources but also lessening researchers’ exposure to toxic chemicals, so called ‘greener’ science. Non-starter reactions can be identified before valuable laboratory time and resources are wasted. Reactions that would have been difficult to study experimentally, forexample because of the time taken to complete or the requirement of toxic chemicals, can be studied with ease on the computer, with mechanistic and chemical insight obtained.
Michael York of Continental Tire North America explains the scientific advantages gained by using computational chemistry, “Experimentation takes manpower, chemicals, equipment, energy, and time. Computational chemistry allows one operator to run multiple chemical reactions 24 hours a day.”
Michael York continues, “By performing the ‘experiments’ on the computer, the chemist
can eliminate non-productive reaction possibilities and narrow the scope of probable
laboratory successes. The end result is a major reduction in laboratory costs (such as
materials, energy, and equipment) and manhours.” See reference [5].
Deepak Srivastava [6], a leading computational nanotechnology expert, describes the
advantages of these computational techniques in nanotechnology, "Theory, modeling, and simulations have provided and will continue to provide insights into what to expect next and verification/explanation of what has been done or observed experimentally. For
nanoscale systems, simulations and theory in fact have provided novel properties that has led to new designs, materials, and systems for nanotechnology applications.”
Srivastava references carbon nanotubes as an example of where these state-of-the-art tools are being used in nanotechnology, “For example carbon nanotubes applications in
molecular electronics or computers were predicted first by theory and simulations, the
experiments are now following up to fabricate and conceptualize new devices based on
those simulations" he states.
References
[1] CMP Cientifica ‘Nanotech – the tiny revolution’, July 2002.
[2] www.rpi.edu/dept/materials/COURSES/NANO/dulgar/nano_index.html
[3] www.intel.com/research/silicon/mooreslaw.htm
[4] Yong Chen, Douglas A. A. Ohlberg, Xuema Li, Duncan R. Stewart, R. Stanley Williams, Jan O. Jeppesen, Kent A. Nielsen, J. Fraser Stoddart, Deirdre L. Olynick, and Erik Anderson, Appl. Phys. Lett., 2003, 82, 1610.
[5] www.accelrys.com/cases/ctire.html
[6] people.nas.nasa.gov/~deepak/home.html
source: Nanotechnology Application Guide, Accelrys.2004
