This blog post explores how invisible nanotechnology can revolutionize daily life while simultaneously posing threats to the environment and health.
Interest in nanotechnology is growing these days. Even if it seems insignificant, simply adding the word ‘nano’ often increases a product’s price. For example, a washing machine with an added ‘silver nano sterilization technology’ function becomes significantly more expensive than a standard model. What exactly is this nanotechnology we frequently encounter in daily life?
First, ‘nano’ originates from the Greek word ‘nanos,’ meaning ‘dwarf.’ One nanometer (nm) is one billionth of a meter, about one hundred thousandth the thickness of a human hair, and roughly the size of three to four atoms. Definitions of nanotechnology vary, but it can be broadly summarized in three key aspects. First, the technology to create minute materials or machines composed of nano-sized substances. Second, the technology to enhance equipment performance by utilizing new physical properties unique to the nano-scale. Third, the technology to measure and predict natural phenomena in the microscopic realm invisible to the naked eye.
Thus, nanotechnology encompasses an extremely vast domain. The U.S. National Nanotechnology Initiative (NNI) outlines three core conditions for nanotechnology. First, research and technological development must occur at the atomic and molecular level within the range of approximately 1 to 100 nanometers. Second, devices or systems with novel properties and functions emerging at this microscopic scale must be created. Third, manipulation and control at the atomic level must be achievable.
The individual who first presented the potential of nanotechnology was American physicist Richard Feynman. He emphasized the possibility of manipulation at the atomic level with the statement, “You could fit the entire Encyclopedia Britannica on the head of a pin.” Following advances in quantum mechanics, nanotechnology entered its formal research phase in 1981 with IBM’s development of the scanning tunneling microscope (STM), which achieved atomic-level resolution. The STM enabled observation of the nano-scale realm invisible to conventional optical microscopes. In 1986, AT&T Bell Labs successfully separated and manipulated atoms using the STM. Subsequent developments like SPM (scanning probe microscopy) and TEM (transmission electron microscopy) further accelerated access to the nanoworld.
Nanotechnology distinguishes itself from other technologies due to unique properties that emerge only at the nanoscale. First, surface characteristics become the primary factor determining a material’s properties. As size decreases to the nanoscale, surface area increases exponentially relative to volume, proving crucial in diverse fields like catalysis, drug delivery, and energy storage. Second, quantum phenomena govern electronic, magnetic, and optical properties. Third, microscopic physical phenomena like Brownian motion play a dominant role, closely linked to nanogears, tunneling effects, and single-electron phenomena.
These characteristics endow nanomaterials with diverse physical properties. For instance, in optical properties, the color changes depending on the nanoparticle size. Metals appear golden at macroscopic scales but can appear red when reduced to sizes below 10 nanometers. Regarding chemical properties, increased surface area enhances reactivity, such as antibacterial effects, which are commercially exploited. Mechanically, a phenomenon occurs where strength increases sharply at specific grain sizes. Electromagnetically, a phenomenon where magnetic properties are maximized at specific sizes has also been reported.
Nanotechnology is a creative technology with limitless potential. Its applications span nearly every industry, including electronics and telecommunications, aerospace, and medicine. In the near future, groundbreaking technologies are expected to emerge in diverse fields such as high-capacity information storage devices, ultra-high-strength materials, nano-catalysts, precise drug delivery systems, genetic engineering, and ultra-fine pollutant removal devices. Furthermore, nanotechnology finds application in everyday life. For instance, self-cleaning surfaces, air purification systems, and customized food production systems are becoming reality.
High-resolution screens, immersive 3D TVs, and vivid art experience technologies can also advance based on nanotechnology. However, behind this bright future lie risks associated with nanotechnology. Concerns have been raised that ultrafine nanomaterials could accumulate in the human body or pollute the environment, and research on this is actively underway.
A prime example is the controversy surrounding the toxicity of carbon nanotubes. Research findings indicate that if this material accumulates in the human body, it could cause long-term health damage. Furthermore, fullerene (C60) can generate reactive oxygen species, and reports suggest that substances like titanium dioxide and diesel particles become more toxic as they shrink to the nanoscale. Cases where nanoparticles contaminate electronic devices and hinder productivity have also been reported, prompting relevant government agencies to initiate environmental impact assessments of nanomaterials.
Consequently, a new academic field called nanotoxicology has emerged. Its purpose is to evaluate the toxicity of nanomaterials and the extent of their effects. Various variables influence toxicity, including not only simple particle size but also chemical composition, functional groups, surface structure, and solubility. Therefore, individual and precise evaluations for each nanomaterial are necessary.
In conclusion, nanotechnology possesses the potential to dramatically transform human life, but thorough research and preparation regarding its risks must proceed in parallel. A balanced perspective and scientific approach are essential for technological advancement to benefit both humans and the environment.
