In this blog post, we’ll explore the concept of nanotechnology, its development, various applications, future potential, as well as safety concerns and limitations.
In this blog post, we will introduce nanotechnology—a concept that is still relatively unfamiliar to many—and examine its basic applications, as well as its limitations and safety concerns.
“Nano” is one of the unit prefixes used in the International System of Units (SI) and represents 10⁻⁹. For example, 3×10⁻⁹ m is 3 nanometers (nm). SI unit prefixes include those for units smaller than 1, such as pico, micro, and milli, as well as those for units larger than 1, such as kilo, mega, giga, and tera. So why, among all these unit prefixes, is nanotechnology specifically recognized as a distinct field of technology? The reason becomes clear once you understand the concept of nanotechnology.
Nanotechnology refers to the technology of synthesizing, assembling, and controlling materials at the extremely small scale of atoms or molecules, as well as measuring and elucidating their properties. In other words, it is a technology that deals with extremely small materials. To handle this microscopic world, a suitable unit of measurement is required, and that unit is the nanometer. Generally, 1 nanometer corresponds to the size of about 3 to 4 atoms lined up side by side.
The first person to mention nanotechnology was Nobel Prize-winning physicist Richard Feynman. In a 1959 lecture titled “There Is Plenty of Room at the Bottom” delivered at the American Physical Society meeting held at the California Institute of Technology, he presented the possibility of creating molecular-scale machines. He also predicted the arrival of the nanotechnology era, stating, “You could fit all the information in the Encyclopedia Britannica on the head of a pin.”
However, at the time, almost no one believed that such technology would actually be realized. This was because the equipment needed to directly observe atoms and molecules did not yet exist. Since it was difficult not only to observe but also to measure and manipulate matter at the atomic and molecular levels, Feynman’s claims were dismissed as unrealistic science fiction.
In 1981, the scanning tunneling microscope (STM), developed by Gerd Binnig and Heinrich Rohrer, paved the way for the direct observation of the arrangement of atoms and molecules. The STM measures surface structures by utilizing the quantum tunneling current generated between a very sharp metal probe and a sample. The tunneling current flowing between the probe and the sample varies depending on the distance between the two objects and the electronic state of the surface. Therefore, by moving the probe to maintain a constant current, the atomic arrangement on the sample’s surface can be observed with extreme precision.
This principle is somewhat similar to the way an LP player’s needle moves along the grooves of a record to read musical information. The LP player’s probe also uses a cantilever structure, and the STM similarly employs a highly precise probe to measure surface information.
Since the development of the STM, various scanning probe microscopes (SPMs) have been developed, including not only the scanning tunneling method but also the atomic force microscope (AFM), which utilizes attractive or repulsive forces between atoms; the magnetic force microscope (MFM), which measures magnetic forces; the friction force microscope (LFM), which measures surface friction; the force-measurement microscope (FMM), which analyzes the mechanical properties of samples; and the electrical force microscope (EFM), which measures electrical properties. The advancement of these instruments has served as a crucial foundation for the rapid growth of nanotechnology.
Nanotechnology existed in various forms in nature long before humans developed it. A prime example is the lotus leaf. The surface of a lotus leaf is densely covered with tiny protrusions, which have the property of not absorbing water easily. Therefore, even when a water droplet falls on the leaf, it does not spread but rolls off, removing dust from the surface in the process. This phenomenon is known as the “Lotus Effect,” and functional paints based on this principle provide a self-cleaning function that washes away dust and contaminants as rainwater runs down the surface.
Another example is the mosquito’s eye. The surface of a mosquito’s eye features a regular arrangement of extremely fine structures that reduce light reflection and increase absorption. Applying this principle can lead to the development of solar cells that absorb light more efficiently.
The scene in the movie ‘Spider-Man’ where the protagonist climbs walls is also frequently cited as a good example of nanotechnology research. In fact, the soles of a gecko’s feet contain countless nano-scale microstructures, which enable the gecko to cling firmly to walls or ceilings by utilizing intermolecular forces. Research is also actively underway to develop new adhesive technologies by mimicking this principle. This field of developing new technologies by mimicking structures and principles found in nature is called nanobiomimetic technology.
Many examples of such nanotechnology are already widely used in everyday life. A prime example is the technology used in computer storage devices to form ultra-thin films just tens of nanometers thick. As semiconductor devices continue to shrink in size, it has become possible to achieve greater storage capacity in devices of the same physical size.
Among the products we encounter in our daily lives, air purifiers are a prime example of nanotechnology in action. Silver (Ag) possesses excellent antibacterial properties but, due to its high cost, its use was limited in the past. However, with nanotechnology enabling the production of extremely small silver particles, it has become possible to achieve high antibacterial effects even with small amounts, leading to its widespread use in various household products.
Nanotechnology is also applied to cosmetics. By using nanotechnology, ingredients that are difficult for the skin to absorb can be formulated into more stable forms or delivered more efficiently, making it a valuable tool in the development of functional cosmetics.
As we’ve seen, nanotechnology is already being utilized across various industrial sectors. So, what kinds of nanotechnologies will be developed in the future?
Nanotechnology is showing even greater potential in the medical field. Active research is currently underway in various areas, such as drug delivery systems, cancer treatment, tissue engineering, and biosensors, and it is expected to evolve into even more precise medical technologies in the future. By leveraging the ability to control materials at the atomic and molecular levels, technologies for more accurate diagnosis and treatment of diseases can continue to advance.
For example, research is already underway on technologies that encapsulate drugs in nanocapsules and deliver them selectively only to the necessary areas. As these technologies advance further, they are expected to enhance the efficacy of drugs while reducing side effects. In addition, the development of ultra-small sensors and nanomedical devices capable of detecting disease signals within the body or measuring biological information in real time is also actively underway.
Carbon nanotubes (CNTs) are also one of the representative materials in nanotechnology. Carbon nanotubes possess both excellent electrical conductivity and high mechanical strength, making them highly promising for use in various industrial fields such as electronics, semiconductors, energy, and composite materials. Although challenges such as manufacturing costs and mass production remain, related technologies are steadily advancing.
Generally, most metals exhibit a characteristic where electrical resistance increases as their length increases. In contrast, carbon nanotubes possess exceptional electrical properties, attracting significant attention as materials for next-generation electronic devices and interconnects. Furthermore, they hold the potential to enable the creation of devices much smaller than those produced by conventional semiconductor processes, making them a key material for the development of high-performance, highly integrated semiconductors.
Carbon nanotubes also exhibit excellent field emission characteristics. Since they can emit electrons even at very low voltages, researchers are exploring their potential applications in various electronic devices and display technologies. As such, thanks to their unique electrical characteristics and outstanding physical properties, carbon nanotubes are the subject of ongoing research across various high-tech industries, including information and communications, energy, healthcare, and aerospace.
Although nanotechnology is a highly promising industry, concerns about safety also exist. Because nanomaterials are extremely small, they may exhibit properties different from those of conventional materials, and in some cases, sufficient verification is needed to determine how these properties affect the human body and the environment.
Due to their extremely small size, concerns have been raised that nanomaterials may pass through cell membranes or migrate to various tissues within the body. The case of asbestos—which was once widely used as an excellent insulator but saw its use severely restricted after it was revealed to cause serious harm to human health—demonstrates just how important it is to verify the safety of new materials.
Even for newly developed nanomaterials, while the raw materials themselves may be safe, processing them into nanoscale particles can cause them to exhibit physical and chemical properties different from those of their conventional forms. Therefore, the toxicity and biosafety of each material must be thoroughly researched and evaluated on a case-by-case basis.
While studies raising concerns about the effects of certain nanoparticles on the human body were published in the past, it is now well established that safety varies significantly depending on the type of material, particle size, exposure level, and usage environment. Consequently, it is difficult to generalize that all nanomaterials are equally hazardous or safe. For this reason, countries around the world are continuously establishing toxicity assessments and safety standards for nanomaterials, and related research is actively underway.
Nanotechnology is expected to continue creating even greater added value as it converges with various industries. Currently, nanotechnology is widely utilized in diverse engineering fields—including semiconductors, electronics, healthcare, energy, the environment, materials, and chemistry—and is creating new industries through convergence with other advanced technologies. Governments around the world, including the South Korean government, are continuously supporting research and development to advance nanotechnology, and many companies are also continuing their research to secure new technologies.
However, for nanotechnology to continue advancing, ensuring safety is just as important as technological development itself. If new nanomaterials are used indiscriminately without a full understanding of their properties, the possibility of unexpected adverse effects cannot be ruled out. The historical case of asbestos—which caused serious harm to human health despite its excellent performance—demonstrates that safety verification must be conducted in tandem with the development of new materials.
For this reason, thorough toxicity assessments and environmental impact assessments must be conducted in parallel during the development and application of nanomaterials. The government must continuously establish safety standards and management systems for newly developed nanomaterials, and companies must also thoroughly verify the physical properties and safety of these materials before developing products. Furthermore, researchers and policymakers must work together to promote ongoing research and institutional improvements to strike a balance between technological innovation and safety.
Although nanotechnology deals with a world so small it is invisible to the naked eye, its impact is immense. The ability to control materials at the atomic and molecular levels opens up new possibilities that transcend the limitations of existing technologies, and it is expected to establish itself as a core technology in various industrial sectors in the future. At the same time, if the technology is developed while giving due consideration to safety and ethical responsibility, nanotechnology will play an even greater role as a key foundational technology that will lead future society.
