In this blog post, we will look at how small but powerful nanotechnology can solve the problems facing humanity, including the environment, energy, and medicine.
The phrase “Fine air bubbles break down pollutants and make them clean!” is often used in washing machine advertisements. A long time ago, in April 2012, the Environmental Machinery Systems Research Laboratory at the Korea Institute of Machinery and Materials announced that it had developed a source technology that uniformly generates up to one ton of nano air bubbles per minute with 40% less energy than conventional technology. Nano- and micro-sized bubbles are hardly affected by buoyancy and can stay in deep water for about three months, creating an environment rich in oxygen and helping various bacteria to grow smoothly. It is said that the decomposition of pollutants is promoted by these bacteria, which can purify water. We often hear in the media that “fine things” or nanotechnology are being used across industries. The smaller the size, the more revolutionary the technology. Let’s take a look at nanotechnology.
Nanotechnology is a term that collectively refers to the technology of creating and manipulating objects at the nanometer level. A nanometer is one-billionth of a meter, and it is about the length of three or four metal atoms lined up. The core of nanotechnology is to manipulate materials at the atomic or molecular level to create devices or systems with completely new properties and functions. This is why nanotechnology has recently been in the spotlight, as it transforms existing materials into innovative materials with new properties. Nanotechnology is a bridge that can overcome various problems and the limitations of existing technologies. In the 21st century, the most pressing issues are hunger caused by population explosion, environmental pollution, energy and resource depletion, and incurable diseases such as cancer. In the industrial sector, we are facing the limits of miniaturization of semiconductors. However, nanotechnology presents the infinite possibilities of materials and is playing a role in turning human imagination into reality. Currently, nanotechnology has broken down the boundaries between disciplines and combined with life, energy, environment, and IT technologies, it has been actively researched for the past 20 years and has reached the stage of industrialization and commercialization. However, this leading science field of nanotechnology is a new field that has only been around for about 30 years. Let’s take a look at how nanotechnology has developed to where it is today.
There are examples of nanotechnology being used in ancient and medieval times, but this article will focus on nanotechnology that has developed alongside modern theories. The person who opened the door to modern nanotechnology was Richard Feynman, a Nobel Prize-winning physicist. He gave a lecture titled “There’s Plenty of Room at the Bottom” at the American Physical Society in 1959. Feynman suggested that if we could control matter at the level of atoms, we could take advantage of the infinite properties of that matter. At the time, many people dismissed this as a far-fetched idea, but he was convinced of the advent of nanotechnology and believed that in the future we would be able to manipulate matter at the atomic level in any way we wanted. Kim Eric Drexler, a nanotechnology theorist, is the person who actively promoted nanotechnology to scientists and politicians and led the revival of the field. He realized the importance of nanotechnology and emphasized the possibilities of nanotechnology through writing and exchanges.
Then, in 1981, Dr. Gerd Binnig invented the scanning tunneling microscope (STM), which can observe the surface structure of semiconductors and conductors at the nanometer level based on quantum mechanical principles. The invention of the STM has made the world of atoms and molecules not only observable but also manipulable. In 1990, IBM’s Dr. Donald Eigler used an STM to move 35 xenon atoms at an ultra-low temperature on the surface of nickel metal to create the letters “IBM.” This is an example that symbolically shows that information can be recorded using atoms, and the invention of this tool has become an opportunity to start full-scale research on nanotechnology.
In 2000, national support for nanotechnology began. The US government launched the National Nanotechnology Initiative (NNI) and allocated a budget of $490 million to nanotechnology research. This marked the beginning of a global race for nanotechnology, which has led to the development of the technology to the present day.
Now, let’s take a look at how scientists have approached the world of nanotechnology, and examine representative technologies and recent research achievements. Scientists have used bottom-up and top-down approaches to approach the nanometer scale. The bottom-up approach is a method of assembling atoms or molecules one by one to create the desired structure. On the other hand, the top-down approach is a method of cutting and shaping large materials to create nanometer-scale devices and materials, and has been used since the Stone Age.
A typical example of a top-down approach is MEMS (Micro-Electro-Mechanical Systems) technology. MEMS is a microelectronic control technology that uses semiconductor processing technology to create micro- or millimeter-sized ultra-small precision machines. These products, which are smaller than a human hair, cannot be seen with the naked eye, so all work must be done on a computer screen. The principle of MEMS technology is to mark the position of a specific material on a thin silicon wafer with a chemical substance and remove the unnecessary parts to form a circuit. Many products are being developed using MEMS technology, such as inkjet printers that can print clearly, nanotechnology pipes that accurately deliver medicine, and medical devices that move paralyzed limbs.
There are several challenges to the advancement of MEMS technology. It must overcome physical phenomena and inertia that occur only in the nano-world, and it requires processing technology that finds suitable materials that will not be destroyed depending on the object. Semiconductor technology using MEMS has now made it possible to manufacture thumb-sized USBs with a capacity of 1 terabyte.
Nano-bio-mimetic engineering is also in the spotlight. This is an engineering that applies nanotechnology to real life, and a typical example is an adhesive pad that mimics the soles of gecko lizards. The fine cilia on the soles of gecko lizards provide strong adhesion using intermolecular attraction, and researchers at Seoul National University have developed an adhesive pad that can be used permanently without the use of glue by mimicking this. In addition, the application of nanobiomimetic engineering is endless, such as making a boat bottom that does not grow barnacles by applying the skin structure of a dolphin, or developing an eco-friendly waterproof paint by imitating the surface of a lotus leaf.
The bottom-up approach involves assembling atoms one by one, which currently only results in simple letter formation, but is expected to enable the creation of nanomachines in the future. BioNano technology combines bottom-up and top-down approaches to develop new biomaterials and devices by analyzing and processing DNA, RNA, and other nanometer-sized biomolecules that make up the human body at the molecular level. A typical application of BioNano is biochips. Biochips are products that integrate biological components into silicon substrates, and they have now been used to develop artificial organs that mimic the liver, neurons, and capillaries.
In addition, bio-nanotechnology is also paying great attention to the research of nanorobots. With the development of biofuel cells and photosynthesis-based technologies, we are approaching an era where nanorobots can enter blood vessels to destroy the causes of diseases and adsorb radioactive substances and discharge them in a harmless state.
In addition, nanotechnology is showing us possibilities that transcend the limits of physical laws and common sense.
