Nanotechnology is one of the three T’s, with applications in new materials, medicine, electronics, and more. However, there are also risks to human health and the environment. As nanotechnology advances, it requires regulation and research.
Recently, the so-called 3Ts (NT: nanotechnology, BT: biotechnology, IT: information technology) have been receiving a lot of attention, and among them, the importance of nanotechnology, which has great value as a basic industry, is emerging. Dr. Eric Drexler, a world-renowned authority on nanotechnology, described nanotechnology as “extremely cheap to produce, easy and fast to use, and the cause of labor surplus, job loss, increased leisure and cultural time, and ultra-fast change.” In the 21st century, technologically advanced countries such as the United States, Europe, and Japan are investing heavily in nanotechnology, and South Korea has designated it as a national priority. As such, nanotechnology has recently become one of the hottest issues in the field of science and technology.
The term nanotechnology refers to the technology of creating or manipulating objects at the nano-meter (nm) level. The word “nano” comes from the Greek word nanos, meaning “dwarf,” and a nanometer is one billionth of a meter, roughly the size of three or four common metal atoms. Thus, at its core, nanotechnology is the manipulation of matter at the scale of atoms or molecules, more precisely than traditional micrometer (μm) manipulation, to create objects or systems with entirely new properties and functions. When we talk about nanotechnology, we can’t forget the American physicist Richard Feynman, who is considered the ‘father of nanotechnology’. His December 1959 lecture at the American Physical Society titled “There’s a Lot of Space at the Bottom” is considered the starting point of nanotechnology. In this talk, Feynman first introduced the concept of nanotechnology to the public by proposing ways to shrink the size of machines, living and nonliving things, at the molecular level. Now, more than 50 years later, nanotechnology has evolved into the cornerstone of all scientific and technological advances.
There are two main technical ways to approach nanotechnology. The first is the top-down method, which is a method of creating nanoscale materials by slicing down from larger materials, and is currently used mainly because the process is relatively easy. This technology is mainly used to make electronic components such as semiconductor devices, displays, and storage, but it is showing its limitations as the size of these components has recently shrunk to within a few tens of nanometers.
The second is the bottom-up method. This method synthesizes materials at a small atomic scale, like stacking Lego blocks, to create the desired nanomaterial. It is much more technically challenging than the top-down method, but it has the advantage of theoretically being able to create any molecule you want. Advances in microscopy technology, such as scanning tunneling microscopes (STM) and atomic force microscopes (AFM), have made it possible to observe materials at the nanometer scale, and bottom-up methods are rapidly advancing. Since bottom-up methods are closer to the source technology, the preferred direction of nanotechnology development is to replace the currently dominant top-down methods with bottom-up methods.
Nanotechnology can be applied to a variety of fields. In the field of new materials, the first to show promise for industrialization, various new materials such as carbon nanotubes (CNTs) have already been developed or are under development. In particular, carbon nanotubes are 100 times stronger than steel, have electrical conductivity similar to copper, and thermal conductivity similar to diamond, the best material in nature. These new materials are already being used in a variety of industries, from hiking poles to spacecraft.
The applications of nanotechnology in medicine and biotechnology are also endless. Since most diseases, including incurable ones like cancer and leukemia, start at the cellular or even smaller molecular scale, theoretically, if molecular-scale nanomachines could be completely controlled by humans, all diseases in the world would be eliminated. Nanotechnology is essential in many areas of biotechnology, such as the use of nanocapsules to maximize the efficiency of drugs, or the development of biochips that can detect DNA, proteins, antibodies, cells, and more for early diagnosis of various diseases, including cancer.
Nanotechnology is also being explored in the semiconductor and electronics industries. Due to the rapid development of the semiconductor industry over the past 30 years, the size of the most common transistor in use today, the metal-oxide field effect transistor (MOSFET), has shrunk to a few to tens of nanometers and is reaching its technical limits. The application of nanotechnology to the semiconductor industry will overcome these limitations and open up the possibility of better semiconductor devices.
The application of nanotechnology is also important in the fields of chemical engineering and energy. The application of catalysts at the nanoscale will bring great advances to the chemical industry, and nanotechnology will also have a major impact on improving the capacity and storage capabilities of fuel cells, which will lead to significant growth in the energy sector.
As you can see, the development of nanotechnology will have a huge impact on our daily lives in the near future. However, there is also the question of whether the development of nanotechnology will only bring convenience to humanity. The world at the nanoscale is governed by different laws of physics than ours, which can create new objects and systems that are different from what we know. For example, gold (Au) is yellowish in the macroscopic world, but when it shrinks down to about 20 nanometers, it turns red. Naturally, biotechnological applications using these nanoparticles are not without risks. In fact, a 2003 NASA study found that injecting tiny amounts of carbon nanotubes into the lungs of rats caused lung tissue damage. Because nanoparticles are so small, they can freely pass through human cells, which can cause a variety of diseases in the human body. In recent years, the dangers of nanoparticles to humans have been emphasized to the point that a new term, nano syndrome, has emerged to describe the syndromes that can be caused by nanoparticles.
The environmental issues that nanotechnology can cause are also important. In a February 2007 white paper, the U.S. Environmental Protection Agency (EPA) warned that when objects made of nanoparticles break, they can release nanoparticles that can contaminate water or air. Considering that Freon gas, which was used as a refrigerant and spray in air conditioners and refrigerators, has been blamed for the ozone layer depletion, the environmental issues of nanoparticles should also be considered.
Nanotechnology can bring tremendous scientific and technological advancements to mankind, but it requires sufficient research and discussion to address the aforementioned issues. Governments need to come up with various regulatory policies. In fact, the U.S. Environmental Protection Agency (EPA) has designated washing machines, air purifiers, etc. that utilize silver nanoparticles as import-controlled items and is strengthening regulations as research shows the dangers of nanoparticles to the human body and the environment. Korea has also amended the ‘Enforcement Rules of the Air Environment Conservation Act’ to regulate nanoparticle emissions from automobiles.
Despite its problems, nanotechnology is an issue that needs to be further researched for the advancement of science and technology. The future of nanotechnology is bright. In his lecture more than 50 years ago, Feynman predicted that with nanotechnology, it would be possible to fit all the information in 24 volumes of the Encyclopedia Britannica on the head of a 1.6 millimeter pin. Medical machines at the nanoscale will travel inside our bodies to repair diseased cells, and we’ll have computers that will be far more powerful than anything we have today. Science fiction may not be far off. It will be based on nanotechnology and the results of theories and experiments in physics, chemistry, electronics, biotechnology, medicine, and other disciplines.
