Nanomaterials | AMERICAN ELEMENTS®

Brief History of Nanotechnology

In his famous talk entitled “There’s Plenty of Room at the Bottom,” Richard Feynman set the stage for research into applied nanoscience. The speech, which was delivered on December 29th, 1959 at the annual meeting of the American Physical Society at the California Institute of Technology, marked a revolution in the way the scientists looked at materials and is widely credited as one of the turning points in the history of materials science that spurred nanotechnology research. At the time, many engineers were interested in miniaturizing devices. For example, engineers of the era talked about making electric motors the size of a fingernail. However, while some scientists were working on devices that could write the Lord’s Prayer on the head of a pin, Feynman was asking why we couldn’t write the entire Encyclopedia Britannica on the head of a pin. Feynman proposed engineering on a radically smaller scale, millions of times smaller than the popular trend at the time, and challenged researchers to achieve that goal.

Manipulation of matter atom by atom was realized in 1986 with the groundbreaking work by Don Eigler of IBM. The research is immortalized in Eigler’s famous “I-B-M” image. His experiment utilized a machine known as a scanning tunneling microscope (STM), the discovery of which earned its inventors a Nobel Prize. An STM is a device that has the ability to map the surface of a material at the atomic level using a needle. Working with an STM that he built, Eigler showed that when he cooled his material to very low temperatures, he was able to use the needle to position individual atoms producing dramatic results. Pursuant to this discovery, an explosion of research has led to a better understanding of nanoscience and its practical application through nanomaterials. American Elements's high purity silica has been used in the production of nanotransistors which are a recent technology inspired by this research.

Applications for Nanomaterials

Nanomaterials have wide ranging and diverse applications in optoelectronics, renewable energy, environmental remediation, chemical catalysis, medical devices, consumer products, and biomedicine. Select applications are briefly discussed below.

Electronics

Nanomaterials have found use in a variety of electronic applications including light emitting diodes (LEDs), thin film devices, transistors, sensors and lasers.

Green Technology & Alternative Energy

Nanostructured metallic and ceramic particles for vastly improve the performance of solid-state alternative energy sources such as fuel cells and batteries, and researchers are actively investigating novel means of utilizing these materials in electrodes, electrolytes, and catalysts that improve on current technologies.

Silicon nanoparticles have been shown to dramatically expand the storage capacity of lithium ion batteries without degrading the silicon during the expansion-contraction cycle that occurs as power is charged and discharged. Silicon has long been known to have an excellent affinity for storage of positively charged lithium cations, making them ideal candidates for next generation lithium ion batteries. However, the quick degradation of silicon storage units has made them commercially unfeasible for most applications. Silicon nanowires, however, cycle without significant degradation and present the potential for use in batteries with greatly expanded storage times.

Rare earth nanoparticles have become particularly important in the development of both cost-effective solid oxide fuel cells (SOFCs) and hydrogen storage technologies based on metal hydrides, including nickel metal-hydride (NiMH) batteries. Materials such as LSM, strontium carbonate nanoparticles, manganese nanoparticles, Manganese oxide nanoparticles, nickel oxide nanoparticles, and several other nanomaterials are finding application in the development of small cost-effective solid oxide fuel cells (SOFCs). Platinum nanoparticles are being used to develop small proton exchange membrane fuel cells (PEM).

Ultra high purity silicon nanoparticles are being used in new forms of solar energy cells. Thin film deposition of silicon quantum dots on the polycrystalline silicon substrate of a photovoltaic (solar) cell increases voltage output as much as 60% by fluorescing the incoming light prior to capture.

Certain nanomaterials serve as effective products for environmental remediation. For example, nickel nanocrystals are a reagent for the dehalogenation of trichloroethylene (TCE) , a common groundwater contaminant. A team of researchers from Singapore and the United States developed a lightweight, porous gel embedded with silver nanoparticles that effectively kill bacteria in tainted water, leaving it purified and potable.

Coatings

Nanoparticles can be applied directly or as an additive to coatings to produce a number of effects on a given surface such as anti-reflective, hydrophobic, adhesive, or anti-microbial properties. For example, liquid repellant coatings are used for numerous applications such as consumer products, vehicles, textiles and more.

Zinc oxide nanoparticles, zinc nanoparticles and silver nanoparticles are often used as anti-microbial, anti-bacterial, anti-biotic and anti-fungal agents when incorporated in coatings, fibers, polymers, first aid bandages, plastics, soap and textiles. For detailed product information on the uses and applications of our Zinc Oxide products, Z-MITE™, see the Z-MITE™ Product Data Sheet.

Industrial Chemistry

For a given amount of material, as particle size decreases, surface area increases. American Elements cerium oxide nanoparticles, platinum nanoparticles, gold nanoparticles, palladium nanoparticles, molybdenum nanoparticles, nickel nanoparticles and iridium nanoparticles have extremely high surface areas which increase their effectiveness as catalysts in a range of chemical synthesis, chemical treatment and petrochemical cracking applications.

Biomedical

The biomedical and bioscience fields have found near limitless uses for nanoparticles. Nanoparticles made of peroxalate ester polymers with a fluorescent dye (pentacene) encapsulated into the polymer have shown to be capable of detecting cancer since hydrogen peroxide is generated by pre-cancerous cells. The dye-bound nanoparticles fluoresce upon coming into contact with hydrogen peroxide which is then detected using medical imaging equipment. When bound to organic molecules, gold and silver nanoparticles have proven to be effective in delivering pharmaceutical drugs to the bodies of cancer patients.

Artificial bone composites are now being manufactured from calcium phosphate nanocrystals. These composites are made of the same mineral as natural bone, yet have strength in compression equal to stainless steel. Tungsten oxide nanoparticles are being used in dental imaging because they are sufficiently radiopaque (impervious to radiation) for high quality X-ray resolution. The group of magnetic nanoparticles discussed above is being used to both kill cancer cells in malignant tumors and in MRI medical imaging. Coating tungsten particles with DNA and injecting them into plant cells or plant embryos allows for the transformation of plant plastids with lower transformation efficiency than in agro bacterial mediated transformation. The anti-bacterial and anti-microbial effects of many nanoparticles such as silver are well understood technology. Fluorescent nanoparticles are being used by biologists to stain and label cellular components. By changing the particle size of quantum dots the specific color emitted can be controlled. With a single light source, one can see the entire range of visible colors, presenting an advantage over traditional organic dyes.

Cosmetics

Nanoscale Z-MITE™ ZnO is being used for its UV absorbing properties to create transparent but highly effective sunscreen. The small size of these particles makes them invisible to the naked eye resulting in a clear lotion.

Nanorobotics

Nanorobots are engineered nanoscale mechanical devices or machines that can be used for applications in medicine, environmental remediation, renewable energy, or computing. Most of these applications are in research and development stages with medical applications, also known as nanomedicine, showing particular promise. Medical researchers at Johns Hopkins University have studied the uses of nanobots for drug delivery, diagnostics and surgical procedures. Another application of nanobots is in developing nanoscale molecular positions systems or conveyor belt-like systems using nanoscale molecules that act like motors when attached to macroscopic surfaces.

Metamaterials

Nanotechnology is a powerful tool in the fabrication of metamaterials: artificial materials designed to exhibit properties not previously found in nature. The potential to tune materials with precise properties for different applications can have a profound impact on nearly every industry.

Safety, Health & Public Policy Issues

As researchers continue to learn more and more about the potential applications of nanomaterials, health officials are also learning about their potential toxicological effects. Indeed, the new field of nanotoxicology—a subfield of particle toxicology—has arisen in order to address the public health concerns related to nanotechnology. The unique dimensions of nanomaterials do present safety and environmental issues that should be addressed responsibly by industry at least in the same manner as fine particulate materials are currently handled under existing health and safety guidelines.

Nanomaterials are classified by size ranges for the purposes of regulatory bodies and investigative studies pertaining to their risks, both to environmental and health outcomes. Numerous articles have been published warning of the dangers presented by unregulated nanotechnologies. Perhaps the most publicized of which is the threat of "Gray Goo," a hypothesized substance resulting from the runaway dissolution of the earth by self-replicating nanobots. While many of these concerns are being studied, the very scale range of these materials do present safety and environmental issues that should be addressed responsibly by industry in at least the same manner as fine particulate materials are currently handled under existing health and safety guidelines.

The Future of Nanotechnology

Nanotechnology is expected to have an impact on nearly every industry. The research community is actively pursuing hundreds of applications in nanomaterials, nanoelectronics, and bionanotechnology. Most current developments in nanotechnology are in the shape and composition of nanomaterials themselves. Researchers are beginning to understand how to assemble complicated nanostructures and accurately predict their behavior, in addition to experimenting with composites of multiple nanomaterials (like graphene and graphene oxide) and fabricating nanoscale structures of materials never created at that size before. Advanced nanodevices and nanoelectronics that utilize these materials are on the horizon, such as nanorobot drug delivery systems, faster computers, and in sensors.

American Elements is actively involved in pursuing promising research to develop equipment and procedures to manipulate single atoms or molecules at a time. In addition, we support the industrial, commercial and academic efforts by supplying the ultra-pure, advanced materials required to perform nanotechnology research.