Strengths of Smallness: Nanotechnology

by Prof. Kirthi Tennakone
(ktenna@yahoo.o.uk),
National Institute of Fundamental Studies

Aesop’s fable, The Lion and the elephant, says: “A lion was enraged by a bird perched on a tree singing aloud. The lion talked to an elephant passing by and said, “Look at that tiny tot, its scream irritated my ears and awakened me. We are huge and rule the jungle but these minuscules are snot scared of us, doesn’t pay due respect. Can we do something to teach them a lesson?” The elephant said, “Don’t underestimate the aptness of small creatures. One day a tiny wasp chased me stinging. I could not do anything about it until the insect flew away on its own. You torture and slaughter sizeable innocent animals. When it comes to smaller ones you are helpless!”

The world has been brought to its knees by the coronavirus, which nearly billion times smaller than the wasp that pricked the elephant!

Humans have invented weapons lethal enough to exterminate their own species, but struggle to fight the nano-sized virus!

Today, with popular drone enthusiasm, helicopters weighing a few grams are in the market. However, a toy helicopter of the size of the wasp with similar sensing ability or combat drones of wasp’s retaliatory capability have not been turned out yet, but the possibility of such machines being created cannot be ruled out.

Nanotechnology aims to find ways of making things scaled down to dimensions of the order of one to several hundred nanometers – one nanometre equals billionth of a meter.

Amazingly, when we scale down dimensions, novel properties absent in larger versions emerge – which physicists refer to as the quantum regime, providing opportunities for more revolutionary developments. Minuteness has peculiarities absent in the big.

The beginnings of Nanotechnology and small things around us

Nanotechnology emerged as a promise and a fashion in the 1980s. However, peculiarities of smallness had been realized much earlier and sometimes seen in matters of everyday life.

Nano-sized objects exist everywhere. Some dust particles in the air, suspensions in water, and viruses in our bodies, have nano-dimensions. Coronavirus measures around 100 nanometers, whereas human cell it invades is larger. A comparative resemblance to Aesop’s bird and lion.

The human body utilises antibodies of size approximately 10 nanometers to fight viruses hundreds of times larger. Here the scales of sizes of things matter, reminding another wise saying of Aesop: A lion cannot catch a gnat, but a spider can.

A lotus leaf withstands wetting by water because the leaf surface is densely packed with extremely thin hair not visible to the eye. However, a dog or a cats get wet instantly when bathed because they have thicker hair spread further apart, in contrast to those on the lotus leaf. Similarly, nano-dimensional spikes on the wings of the dragon fly inhibit growth of bacteria. Face masks mimicking dragon fly wings would be in the market soon.

Veddas were the first to attempt art of nanotechnology in Sri Lanka

A remedy for snake bite practiced by Veddas has been to place the so-called snake stone at the site of the strike. The stone attaches itself to the wound and is said to fall after extracting the venom. Snake stones were made by grounding a piece of charred bone to a rounded shape. Around 1850, Emerson Tennent, the Colonial Secretary of Ceylon dispatched samples of snake stones to the illustrious British scientist Michael Faraday for examination. Faraday found that the stone was porous and constituted of minute openings. He suggested the pores may be sucking venom via capillary forces. Recent investigations have shown that although the hypothesis stands theoretically sound, the amount of venom extracted would not be sufficient to reverse poisoning. Faraday did many things which stand as benchmarks of nanotechnology in present day terminology. An iridescent red solution of gold nano-particles he made 150 years ago remain intact in a bottle displayed at the Faraday Museum, London.

The man who enlightened the world of the potential of nanotechnology was the American theoretical physicist Richard Feynman. In a famous talk given at the California Institute of Technology in 1959, Feynman pointed out that if ways were found to fix different atoms and molecules in appropriate positions just like building a house or a machine out of component parts, marvelous things could be done – for example Encyclopedia Britannica may be encoded in a device of the size of a pin head. Now, we know this happens in nature. Human DNA encoding all information necessary to make a man or a women, weighs about one trillionths of a gram! At the time Feynman gave his lecture, tools were not available to manipulate assemblies of atoms and molecules. Around the mid-1980s, basic instruments needed for the purpose were developed, giving a kick start to nano-science and technology.

Progress in nanotechnology

Scientific discoveries and technological innovations progress hand in hand. New discoveries pave way for inventions. That, in return, facilitate technological advancements providing tools necessary to foster new discoveries? With the strength of modern instrumentation made available since early 1980s, the implementation of Feynman’s ideas seemed to be in horizon. Research in the area gained momentum; nanotechnology institutes and university departments in the theme mushroomed everywhere. Some scientists changed their colour like chameleons, claiming they were nanotechnologists. The result has been a proliferation of incremental advances in making smaller and smaller gadgetries. If not for the yet unresolved question supplying power, machines of the size of a grain of sand are now feasible. Engineering has reached an unprecedented degree of precision. Nanotechnology’s coveted gadget, the scanning tunneling microscope, can map surfaces to atomic dimensions. The gravitational wave detector measures the changes in a thousand kilometer distance to an accuracy more than one billionths of a millimetre. Even with this level precision now available, nanotechnology hasn’t achieved breakthroughs of the magnitude comparable to the development of the transistor or discovery of DNA. Major advancements take time and for that we need creative minds and preparedness.

Graphene: Nanotechnology’s prodigious child

Nanotechnology’s prodigious child is graphene – a one atom thick sheet of carbon atoms bonded to each other – pack of these sheets being graphite we have as a mineral. For a long time, researchers thought it would be a prohibitively impossible to pull out a sheet of graphene from graphite. In 2004, Andre Grim and Kostya Novoselov at the University of Manchester succeeded in doing this by using an ordinary sticking tape and won the Nobel Prize-demonstrating that to arrive at groundbreaking discoveries, sophisticated brains are more important than institutions with shining floors housing state-of-the- art instrumentation.

Graphene promise miracles. As a consequence of extreme thinness, it behaves very different from graphite. Mechanical strength and electrical properties of graphene surpass other materials. Electrons travel so fast in graphene invoking Einstein’s relativity into material science for the first time. Possibilities of applications of graphene in diverse variety of areas stands sky high.

Graphite is a basic raw material used to manufacture graphene. Sri Lankan vein graphite stands topmost in purity and other properties for the purpose. Graphite is a resource-limited critical mineral; the demand will escalate exponentially, once graphene based electronic become a practicality. Sri Lanka needs to prepare for this eventuality not only by manufacturing graphene but gaining know how make such electronic devices ourselves. Advanced fundamental research in modern context as well as higher education with stronger emphasis on physics, mathematics and electronic engineering is a prerequisite.

Periods of history signifying major technological advancements are often named after the use of materials. Future is destined to be the graphene age – present being silicon and past ages – iron and stone. As life is based on carbon – naturally non-toxic and recyclable to harmless constituents – a plausible solution to environmental sustainability would be to adopt carbon as primary structural and electronic material.

Nanotechnology is an amalgamation of many disciplines

Nanotechnology is an amalgamation of many disciplines––physics, chemistry, biology, engineering and medicine––with physics in the forefront. Excellence in these fields and team work determine success.

Improvements to existing products by incorporation components which literally implicate a nano-scale appear in the market – sometimes trivialities are exaggerated as nanotechnology.

Developing a marketable commodity benefitting the society, significantly impacting an economy, is not an easy task. Inventions or new ideas need to have a credible scientific basis. These generally follow from publications in peer reviewed journals and subsequent reconfirmation in the light of pros and cons. Patents safeguards the originality of an invention for a specified period of time. However, publications in print and patents alone does not guarantee a profitable marketing of a product. Unfounded statements based only on these outputs confuse the policymaker and the general public.

Nanotechnology is not everything. All issues on earth cannot be solved with its help. In less advanced countries, there exist many gaps in established technologies, greatly limiting industrial expansion. Sri Lanka still lacks centuries old technologies of fertilizer manufacturing. It is most unlikely that a quantum jump to nanotechnology would solve our fertilizer or energy problem. Proven conventional industries need to be established first.

Nanotechnology in developing countries

It is heartening that developing countries including Sri Lanka embarked on the theme of nanotechnology without awaiting the follow-up of the accomplishment of the West. Starting with research carried out at the Department of Physics University of Ruhuna in 1980s and Institute of Fundamental Studies, Kandy, Sri Lanka pioneered the nano-solar cell concept referred to as the “Dye-sensitized Solid-State Solar Cell” subsequently experimented in many leading laboratories in the world.

We have laboratories dedicated to nano-science and technology at Institute of Fundamental Studies, Sri Lanka Institute of Nanotechnology, Industrial Technology Institute and Universities of Colombo, Peradeniya, Jaffna and Wayamba. Publication output from in the theme originating from these institutions is commendable.

Developing nation’s emphasis on nanotechnology is manifestly evident from the percentage share of research publications on this theme out of the total number originating from each country. According to 2019 statistics, this quantity ranks highest for Iran. Followed by Saudi Arabia, India, China, Egypt and South Korea in that order. The value of the aforesaid percentage for United States and United Kingdom are much lower (5.5 and 4.7 respectively) because these countries generate vast number publications in other areas. Nevertheless these two countries have excelled in major innovations and original findings in nanotechnology as well as other scientific endeavors – notably frontier fundamental research.

Statistics deliver an important message to developing nations. They have invested much in a thematic fashion expecting returns – immediate economic benefits. Their achievements are mostly incremental contributions to findings earned elsewhere – notably those regions where the percentage share of publications was less. Have they gained economic returns? The United States and other countries in Europe emphasizing basic science have done better in technology and science of the nano-scale. Developing countries will do better in gathering fruits of nanotechnology by paying more attention basic research and education and closing the gap in conventional advanced technology. The shyness to challenging fundamental studies and the habit of entertaining easier themes not mandated on the pretext of usefulness deters scientific progress – the result is neither advancement in knowledge nor applied innovations.

Quality research as well as good teaching determines the technology’s future and economic returns. Researchers should not always go for easy targets permitting quick results, but commit to challenges that require years of hard work. Similarly, commitment to teaching without repeating age old notes, sharpens understanding. As Feynman said, “If you want to learn something teach it.” Absence of these essential qualities is the root cause of the failure of scientific policies, projects and institutions.

Consequent to the pandemic the world faces an unrivalled crisis created by a nano-sized organism. Salvage is science and nothing else. Those who exalted superstition downplaying science as something Western, now appeals to science. Developing countries awaited vaccines and cures from West. Time of the pandemic would be an opportune moment for us in the developing world to analyze why we lag behind West when it comes to science. How should we prepare to face future calamities ourselves?