In this blog post, we will look at the innovations and potential risks that nanotechnology will bring to science, industry, and everyday life, and shed light on its impact on future society.
When K. Eric Drexler first popularized the term “nanotechnology” in the 1980s, he proposed ideas for molecular-sized machines, motors a few nanometers wide, robotic arms, and even entire computers smaller than cells. Drexler spent the next decade describing and analyzing these amazing devices and responding to accusations that his research was science fiction. As nanotechnology became a widely accepted concept, the meaning of the word changed to refer to simpler technologies on the nanometer scale.
Most of the word “nanotechnology” today was coined by Drexler. Nanotechnology in the traditional sense meant building things from the bottom up with atomic-level precision. This theoretical capability was envisioned early on by Richard Feynman, a renowned physicist who won the Nobel Prize in Physics in 1959. “I would like to build a billion tiny factories, all working simultaneously, each making models of each other… As far as I can see, the principles of physics do not preclude the possibility of manipulating things at the atomic level. It is not an attempt to violate any laws; it is possible in principle, but in practice we have been too big to do it.”
The word “nano” itself refers to a length scale that is a thousand times smaller than the micro scale. One nanometer is one billionth of a meter. The nanometer unit has traditionally been associated with the electronics industry. Viruses and DNA are examples of natural objects that are nanoscale. In contrast to these molecules, human cells can seem enormous. The term nanotechnology refers to the engineering, measurement, and understanding of nanoscale materials and devices. The nanoworld is very different from the world around us. In the nanoworld, physical models known as quantum mechanics may be more dominant than classical physics. Quantum mechanics is a large and complex field in which matter can behave very differently in terms of its electrical and mechanical properties. Other properties, such as temperature, cannot be defined in the classical sense and must be considered in new ways. These phenomena have a major impact on the electronics industry, as quantum electronics could unlock computing power that has not yet been developed.
Nanotechnology represents an entire field of science and engineering, not a single product or family of products. As such, there are many different types of nanotechnology, and many applications associated with each type. In addition, there are many types of nanoscale objects around us, both natural and unnatural. For example, embedded nanotechnology covers electronics, optoelectronics, building materials, and sports equipment. Films and coatings cover self-cleaning coatings, waterproofing, antibacterial coatings such as medical equipment, food containers, and consumer electronics. Biologically natural nanotechnology covers DNA and viruses. Unintentionally created particles deal with metal smelting, fossil fuel combustion including gasoline and diesel fuel. Natural particles deal with particles emitted from volcanic eruptions and forest fires. Manufactured particles deal with food and cosmetic additives such as sunscreen, antibacterial applications, and pollution purification. Nanoelectromechanical systems (NEMS) deal with drug delivery and diagnostic smart sensors.
There are many fields of nanotechnology. For example, microelectromechanical systems, or MEMS for short, involve research into safe drug delivery processes and micro-mimetic robots. Manipulating flat, single-crystal atoms at the atomic level and creating features at the atomic or “nano” scale is now a proven technology. The catalog of applications for nanotechnology continues to grow. The National Nanotechnology Initiative, which coordinates nanoscale science at 26 US federal agencies, defines nanotechnology as “the understanding and control of matter at the scale of 1 to 100 nanometers, enabling new applications through unique phenomena.” Nanotechnology is unique in that it enables many uses and applications that were not possible with conventional materials. Applications that utilize the chemical properties of materials require less nanomaterial than conventional materials. The chemical reactivity of a material is related to its surface area relative to its volume. The surface area per unit volume of nanoparticles is enormous.
The amount of nanoparticles in a material can be determined by the mass fraction of nanoparticles, which refers to the weight of nanoparticles relative to the total weight of the material, or by the “particle number distribution,” which refers to the number of nanoparticles relative to the total number of particles. Most measurement methods produce a strength-weighted size distribution. There is a relationship between these different size distributions for all materials, but this relationship is generally unknown and therefore different size distributions cannot be converted directly. Many materials can be designed as nanoparticles, including silver, carbon, zinc, silica, titanium dioxide, gold, and iron. The most common materials are silver, carbon, zinc, silica, titanium dioxide, gold, and iron. These materials are typically small clusters of atoms. Carbon can also be made into hollow spheres or tubes of atoms, collectively known as fullerenes. Silver is effective at killing microorganisms and is used to maintain hygiene in food appliances, while iron is used to remove contamination from polluted soil. Fullerenes have a variety of electrical and mechanical properties and have many potential applications.
The greatest advantage of nanotechnology stems from the fact that it greatly expands the toolkit commonly used in materials science by allowing the essential structure of materials to be adjusted at the nanoscale to achieve specific properties. Nanotechnology can be used to effectively create materials with a variety of properties, such as being stronger, lighter, more durable, more reactive, more flexible, or better electrical conductors. Nanoscale additives in polymer composites used in baseball bats, tennis rackets, motorcycle helmets, car bumpers, luggage, and power tool housings. Nano-scale additives can simultaneously improve light weight, stiffness, durability, and resilience. Nano-scale surface treatment of fabrics helps prevent wrinkles, stains, and bacterial growth, and reduces ballistic energy deflection in personal body armor. Nano-sized thin films on eyeglasses, computer and camera displays, windows, and other surfaces can provide functions such as water repellency, anti-reflection, self-cleaning, UV or infrared resistance, anti-fogging, antibacterial, scratch resistance, and electrical conductivity. Nano materials in cosmetics provide transparency, coverage, cleansing power, absorbency, customization, antioxidants, antibacterial properties, and other health benefits in sunscreens, cleansers, complexion treatments, creams and lotions, shampoos, and specialty makeup. These are just a few of the benefits that can be achieved through nanotechnology.
In addition to these benefits, nanomaterials can pose threats to our health and safety. Health and safety aspects include the intrinsic hazard patterns of nanomaterials, exposure at the worker, consumer, and waste disposal stages, and applicable risk management measures. The risk is determined by the properties of the substance itself. However, these hazards only lead to health or environmental risks when part of the human body or the environment is exposed to nanomaterials and suffers corresponding adverse effects, and the risk is determined by a combination of the hazard and the likelihood of exposure. Hazard patterns vary greatly between nanomaterials. In its opinion of January 19, 2009, the Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) concluded that: “Health and environmental hazards for a wide range of manufactured nanomaterials have been identified. The identified risks indicate potential toxic effects of nanomaterials on humans and the environment. However, not all nanomaterials cause toxic effects. The hypothesis that smaller size leads to higher reactivity and toxicity cannot be supported by published data. In this respect, nanomaterials are similar to conventional substances, some of which are toxic and some of which are not. As there is no paradigm that can be generally applied to the identification of hazards of nanomaterials, a case-by-case approach to the risk assessment of nanomaterials is recommended.” Monitoring developments in this field will be key to keeping the highest potential risks at the forefront of risk assessment. A recent review of the potential adverse effects of nanotechnology suggests that nanomaterials may pose risks to human health and the environment in certain situations. These findings underscore the important role that nanotoxicology research can play in the responsible development of nanotechnology and the significant benefits that nanotechnology can offer to society.
“I am hopeful that nanotechnology will enable governments to put structures in place, both domestically and internationally,” said Peter Grutter, a physicist at McGill University. In fact, nanotechnology has implications that go beyond what we are discussing here. The discovery and exploitation of new properties of materials opens up almost unlimited applications. That is why nanotechnology is called a ‘platform’ technology that can be easily combined and integrated with other technologies to transform almost everything. The Nano Frontier participants focused on key areas where nanotechnology is expected to have a major impact in the near future. The impact of nanotechnology on many other areas, such as textiles, paper, food manufacturing, and agriculture, was not discussed in depth. Although advances in computing and electronics are progressing rapidly, these applications of nanotechnology were not selected as a focus for this conference.
