Nanomaterials: Unique Properties and Diverse Applications Uncategorized

Nanomaterials: Unique Properties and Diverse Applications

Nanomaterials Products and Applications The smallest nanomaterials have unique properties not found in bulk materials or in molecular structures. The precise shape and composition of a nanomaterial determines its physical and chemical properties. These properties are being used in products such as polymer nanocomposites structural parts, solar cells that generate more energy and carbon nanotube sheets that improve the performance and durability of airplanes, cars and power tools. ChemicalsChemical nanomaterials are used to enhance a wide range of consumer products and industrial applications. They are also used in catalysis, environmental sensing, and other technological functions. Nanomaterials can be produced by cutting down macro structures to the nanoscale (top-down approach) or assembled from atoms and molecules. The latter process is called bottom-up manufacturing. Nanomaterials are found in a number of household and industrial products, including cleaning supplies like degreasers and stain removers; anti-corrosion coatings for tools and machines; lubricants that reduce wear; and self-cleaning paints that seal dirt inside a sealed film. They are also used in modern, human-safe insulation, and carbon nanotubes that bend when electrically charged, allowing lighter bats and aircraft wings. In addition to this, they can be used in catalysis to boost chemical reactions and avoid pollution. ElectronicsIn electronics, nanoscale materials can be used to improve the performance of devices such as displays for smart phones and e-book readers. Examples include semiconductor nanomembranes, conductive inks, and flexible display screens. Carbon nanotubes are another emerging nanotechnology with a wide range of potential applications. These microscopic tubes have exceptional physical properties, including thermal conductivity that rivals diamond, mechanical strength that outperforms steel, and high electric conductivity. Nanoparticles are being developed for medical applications, such as incorporating gold into nanoparticles that bind to cancerous cell growths or using silver nanoparticles in bandages to smother harmful bacteria. Other applications include enhancing agricultural cultivation by helping to reduce pesticide use, and improving transportation infrastructure through sensors and vehicles that can communicate with one another. This technology also makes it possible to harvest and store renewable energy. Health CareThe health care industry is developing a wide range of nanomaterials for use as medical devices and pharmaceuticals. These nanomaterials are being used to deliver drugs directly to cancerous cells, or to the lining of arteries to prevent blood clots from forming. Nanomaterials can appear naturally or be engineered to perform a specific function. They vary in chemical composition, primary particle size and shape, surface coatings, and strength of particle bonds. Examples include quantum dots, silver dendrimers and carbon fullerenes (Buckyballs), and carbon nanotubes. Some nanomaterials are ingested or inhaled, and may end up in aquatic ecosystems, where they could cause harm. The NTP’s three core agencies — NIEHS, the National Center for Toxicological Research at the Food and Drug Administration and the Centers for Disease Control and Prevention — are working together to develop scientific methods to evaluate these materials for their potential hazards. AerospaceNanotechnology is used to make products that are lighter, stronger, more durable or have better electrical or thermal conductivity. For example, carbon nanotubes help make bicycle frames and tennis rackets lighter and more stiff. They are also used in epoxy coatings that make kayaks and boats faster and more stable in water, and to keep golf balls bouncy. EPA scientists are working on ways to use nanotechnology to monitor chemicals and harmful substances in the environment, and to identify potential hazards. They are developing nanoparticle-specific models to understand how the unique properties of these particles may impact their release, transformation and exposure in the environment. Other projects include a nanotech sensor that can detect chemical and biological agents in the air or soil. And they are studying self-assembled monolayers on mesoporous supports and dendrimers, and carbon nanotubes to see if these materials can be used for toxic site remediation. EnergyEnergy scientists are finding new ways to use nanomaterials to improve the efficiency of existing energy-generating methods and find new ways to create power. They're working to develop insulating and conductive nanomaterials that are lighter, stronger, and have less chemical reactivity than their bulk counterparts. The results of these efforts can be seen in products such as a solar steam generator that uses sunlight to produce electricity, and lubricants made with carbon nanotubes that reduce friction without increasing energy consumption. Researchers are also working to create solar panels that are lighter and more efficient and to find ways to harness the solar radiation that bypasses Earth each day. Other examples include clear nanoscale films that make eyeglasses, computer and camera displays, and windows water- and residue-repellent, antireflective, self-cleaning, resistant to ultraviolet or infrared light, or electrically conductive; semiconductor quantum dots that enable TVs and displays to display more colors with greater efficiency; and batteries that charge faster, hold more power, and last longer. Return to the home screen…
Nanomaterials in Chemistry: Small-sized particles with unique properties Uncategorized

Nanomaterials in Chemistry: Small-sized particles with unique properties

Nanomaterials in Chemistry Nanomaterials are particulate materials that are smaller than the wavelength of light. They can be created naturally or engineered. Nanoparticles are characterized by their surface area and specific reactivity. They can also assemble into larger structures to create new materials. Examples include the atom-thick carbon allotrope graphene rolled into soccer ball-shaped molecules, known as fullerenes or buckyballs. Other examples are quantum dots, which have been used in composites and solar cells. SynthesisIn chemistry, nanomaterials refer to materials that exhibit new or enhanced properties due to their small size. Nanomaterials can occur naturally or can be engineered to perform a specific function. Researchers use various techniques to control the composition, size and surface chemistry of different nanomaterials. These techniques start with molecular precursors and can result in a wide variety of materials with diverse properties. As a material becomes smaller, more of its atoms are located on the surface, increasing the ratio of surface area to total volume. This makes nanomaterials highly reactive. PNNL has several aberration-corrected scanning transmission electron microscopes and atomic force microscopy capable of providing atomic-level images of nanostructured materials. One example of a nanomaterial is box-shaped graphene (BSG), which is formed by mechanically cleaving pyrolytic graphite. BSG has unique physical properties, including electrical conductivity and transparency, and can be used in a variety of applications. It also acts as a catalyst in chemical reactions. CharacterizationA chemistry professor at the University of Massachusetts Lowell, Mingdi Yan, describes nanomaterials as "natural, incidental or manufactured materials with particle sizes where 50% or more of the particles have one or more external dimensions in the range 1 nm - 100 nm".1 Nanomaterials can be classified into two broad categories depending on how many of their dimensions fall within this range. Zero-dimensional (0D) nanomaterials have all of their dimensions in the nanorange and include nanoparticles, nanowires, and nanotubes. One-dimensional (1D) nanomaterials have one dimension outside the nanorange and include nanofilms and monolayers such as graphene. Compared to macroscopic materials, nanomaterials require unique and sophisticated tools for their characterization. These include a range of analytical techniques that depend on changes in a physical property as the particle size decreases, such as QCM and surface plasmon resonance (SPR). Each tool has its own underlying principles and limits that should be understood. This information is crucial to understanding the interactions of nanomaterials with their environments and biological systems. AssembliesNanoscale materials possess unique physical properties that can improve a wide range of technological applications, including photovoltaics, plasmonics, and magnetic storage. However, precise control over the spatial distribution and orientation of these materials is often requisite to fully realize their potential. PNNL researchers are developing methods for generating nanomaterial assemblies with specific geometric and compositional arrangements across macroscopic areas and volumes. This is accomplished via a variety of strategies, including manipulation of interparticle physical interactions, modification of nanoparticle surface chemistry, application of external fields, and utilization of physically or chemically patterned templates. These assembly approaches are important because they can reduce the amount of material needed for a given function. For example, inks made from cyanobacteria and used for dyeing fabrics could use nanometer-scale particles to provide greater color intensity and durability. Additionally, aqueous solutions of protein-based nanoparticles can self-assemble into spheres (called vaults) with hollow cavities that are useful for encapsulating cancer chemotherapeutics or nucleic acids. ApplicationsThere are a wide variety of applications for nanomaterials, either as fixed (for example attached to a surface or within in a composite) or free. They may be used for catalysis, coatings, sensors, adsorption and drug delivery. Nanomaterials can be constructed by bottom up techniques, where they are assembled atom by atom or molecule, such as crystal growth for the semiconductor industry and chemical synthesis of large molecules. They can also be constructed through a top down process, such as nanoscale self assembly of polymeric molecules or hierarchical adsorption to a substrate. The ability to control the size of a nanomaterial opens up new possibilities for use in chemistry. For example, glass fragments with nanoparticles of silver and gold give a unique colour, and a coating with carbon nanotubes improves the strength of yacht masts. A range of traditional techniques can be used to characterize nanomaterials, including transmission electron microscopy and scanning electron microscopy, as well as dynamic light scattering and spectroscopy. Return to the home screen…
Advantages and Disadvantages of Nanomaterials: Impact on Industries and Society Uncategorized

Advantages and Disadvantages of Nanomaterials: Impact on Industries and Society

Nanomaterials Advantages and Disadvantages Nanomaterials are atom-sized particles and tubes that can be used to make new products. They are used in products like strong and light materials, and super-efficient solar cells. Scientists are also working on using them to help in medicine, for example delivering drugs to specific cells and in environmental clean up. But there are some disadvantages to this technology. AdvantagesInorganic nanomaterials such as carbon nanotubes and graphene are used to create more powerful microchips, lighter and more conductive semiconductors, and stronger and more durable batteries. Carbon nanotubes are also being used to create a more efficient solar cell that can double the amount of energy it converts from sunlight. The unique structure of nanoparticles allows them to absorb, scatter, or capture a wide range of electromagnetic frequencies, giving them an enormous potential for applications in communications and signal processing, medical imaging, and drug delivery. The large surface area-to-volume ratio of nanoparticles also gives them an advantage in the production of materials that have active surfaces with high efficiencies, such as catalysts and solar cells. PNNL's researchers study nanomaterials using advanced microscopes, including aberration-corrected scanning transmission electron microscopy and atomic force and scanning tunneling microscopes. Using these techniques, researchers can determine the exact composition and structure of nanomaterials at the atom level. This information is critical to understanding how the unique properties of these new materials arise and how they can be harnessed for industrial applications. Nanotechnology is a relatively new field, and many governments around the world are still developing standards and regulations for their safe use and disposal. Some nanoparticles can be toxic when inhaled or ingested, and it is important to take precautions when handling and disposing of these materials. The relative novelty of these materials also limits the availability of comprehensive testing, and there is not enough data on their long-term effects to assess risks. In the medical field, nanotechnology has been instrumental in developing new vaccines and drugs. The size of nanoparticles allows them to easily pass through cell membranes, allowing them to reach and interact with the molecules inside the body. This has allowed doctors to treat diseases that would otherwise be untreatable. Nanotechnology is transforming a number of different industries, including manufacturing, food production, mining, and electronics. As these technologies become more widely available and affordable, they may significantly reduce the need for labor-intensive work and increase economic growth worldwide. Some critics worry that the rapid development of nanotechnology will lead to job losses in a variety of sectors. However, scientists believe that the increased efficiency and cost-effectiveness of nanotechnology will offset these losses. This will lead to a more stable economy that can better adapt to changing conditions and provide opportunities for more people around the world. In addition, alternative energy sources that are more efficient and require less fossil fuel could replace some of the need for traditional oil and coal. The global economy will then be less dependent on the price of oil and other non-renewable resources. This will also help to mitigate environmental impacts from these non-renewable resources. This will benefit all of humanity, especially in poorer countries where the need for oil and other resources is greatest. This will allow those nations to invest in more education and other infrastructure to promote social development. It will also lead to cleaner, safer, and more environmentally friendly products. This will improve the quality of life for millions of people around the world. Keep reading…
Exploring the Diverse Applications of Carbon Nanomaterials Uncategorized

Exploring the Diverse Applications of Carbon Nanomaterials

Applications of Carbon Nanomaterials Since the discovery of fullerenes in 1985, carbon nanotubes in 1991 and graphene in 2004, their unique properties have been exploited for technical, medical and environmental applications. Carbon-based nanomaterials can be combined with molecules via strong covalent bonds which yield kinetically stable compounds. Typically, however, only pristine particles are used in studies on their impact on living organisms. This approach hardly reflects realistic natural conditions. PhysicalThe unique physical properties of carbon nanomaterials enable them to be used as components in very sensitive sensor devices that can detect low concentrations of chemical compounds. Such sensors have a broad range of environmental applications. They can replace activated carbon (AC) in wastewater filtration, and they are also useful in agricultural processes. Carbon nanotubes are tubes made of carbon with diameters in the nanometer range. They have superior mechanical strength and electrical conductivity. They can be single-walled or multi-walled. Single-walled ones can be zigzag or armchair-shaped. They can have surface functional groups that increase their chemical reactivity and add new properties. Based on their chiral vector, they can be metallic when n is equal to 1 and semiconducting when n is equal to 2 or 3. The morphology of carbon nanotubes determines their absorption spectra. ChemicalCarbon nanomaterials exhibit remarkable chemical properties that can be exploited for a broad spectrum of applications. These materials have the potential to replace traditional activated carbon (AC) in wastewater filtration systems and as promising drug/gene delivery systems. Carbon can exist in a number of molecular forms (allotropes) that differ in their properties. The most well-known are diamond and graphite. Carbon nanomaterials can be tube-shaped, horn-shaped or spherical and are also referred to as fullerenes. The structure of a carbon nanomaterial determines its physicochemical characteristics, with the most important being solubility and surface chemistry. In addition, the morphology of a carbon nanomaterial can be modified by chemical functionalization. For example, by oxidation of carbon nanotubes, carboxylic groups can be introduced on their surfaces to enhance solubility. ElectricalCarbon atoms can form three different allotropes that differ in their strength, electrical properties and other characteristics. Two of these allotropes, graphene and carbon nanotubes, are attracting great interest because they can be used to make incredibly strong, light, conductive materials. The shapes of carbon nanoparticles determine their electrical properties. Particles that are tube-shaped are called carbon nanotubes, those that are horn-shaped are called nanohorns and those that are spherical or ellipsoidal belong to the group known as fullerenes. Single-wall carbon nanotubes that are metallic have the highest electrical conductivity of any material. SWCNTs that are semi-conducting have lower conductivity than metallic ones. The chirality of the tubes also affects their conductivity. BiomedicalCarbon nanomaterials such as fullerenes, graphene and carbon nanotubes exhibit unique mechanical, electrical, thermal and chemical properties that make them attractive candidates for many biomedical applications. These include drug delivery, tumor therapy, targeted bio-sensing, tissue engineering and cellular imaging. A major challenge in the field of biomedical applications is the toxicity of carbon nanomaterials, which can be caused by the production and processing techniques as well as by their intentional or accidental release into natural and agricultural ecosystems. To address this issue, the surface of carbon nanomaterials can be functionalized in order to increase their affinity for adsorbates. This can be achieved by adding ligands, polymers and other nanoparticles, which also improve their biocompatibility. In addition, the size of carbon nanomaterials can be adjusted to achieve desired target tissue accumulation. EnergyCarbon nanomaterials - including nanohorns, nanofibers and the more popular carbon nanotubes have unique properties which have opened up new areas for research. They all share the sp2 hybridization of carbon atoms, a hexagonal pattern and high mechanical strength but their individual sizes, shapes and chirality distinguish them from one another. The discovery of multi-wall and single-wall carbon nanotubes (MWNTs and SWNTs respectively) brought a new dimension to the field. They resemble a graphene sheet rolled into a tube and capped at both ends. Carbon nanoparticles exhibit remarkable adsorption capabilities and can be employed in many different environmental applications. In particular, they are able to effectively remove and monitor pollutants in urban and agricultural ecosystems. They can also be used to detect and remove contaminants in food chains with potentially hazardous effects on living organisms. Dive deeper to discover more…
The History and Applications of Nanomaterials Uncategorized

The History and Applications of Nanomaterials

Nanomaterials HistoryNaturally occurring nanomaterials have unique structures and properties. Examples include the structure of foraminifera, viruses, gecko feet, the wax crystals covering lotus and nasturtium leaves, and the silk of spiders and geckoes.The American physicist Richard Feynman introduced the concept of nanotechnology in 1959. He envisioned building products atom-by-atom and down to the molecular level.HistoryIn 1959, physicist Richard Feynman first introduced the concept of nanotechnology when he presented his famous lecture, "There's Plenty of Room at the Bottom." This new field of research centers on materials that are small enough to be seen only with an electron microscope.Artisans in Deruta, Italy, during the fifteenth and sixteenth centuries practiced early nanotechnology to create dramatic iridescent or metallic glazes for ceramics. These effects are due to varying the size of metal particles suspended in the glazes, which scatter light differently at different wavelengths for shimmering color and luster.But the craftsmen who made these glazes were not nanotechnologists, because they did not know that they were creating a material at the nanoscale. A surviving example of their work is the Lycurgus Cup, which looks slate green under direct light but glows red when lit from the inside. This phenomenon, called dichroism, is due to gold and silver nanoparticles in the glass.SynthesisThe synthesis of nanomaterials is the process by which atoms or molecules are assembled into structures with dimensions in the range of 1 to 100 nm. These structures exhibit distinct properties that are a result of their size.Craftsmen in the fifteenth and sixteenth centuries of Deruta, Italy used a form of nanotechnology to create dramatic iridescent and metallic pottery glazes. They did this by incorporating silver and gold particles that scatter light at different wavelengths, producing the color variation.Another example of nanotechnology is the carbon-based material known as fullerenes. When these are injected into lymphoma cells, they prevent the cancerous cell from "feeding" on actual cholesterol, starving it to death. The synthesis of these materials requires the use of special solvents, and the process is expensive. Plasma and flame pyrolysis are two popular methods for making nanoparticles, but they don't offer much flexibility when it comes to design precision or customization. This is one reason why many companies that experiment with this type of synthesis turn to Cerion for help and advice.ApplicationsA nanomaterial’s unique properties can be applied to a variety of products. For example, carbon nanotubes are being used in a number of consumer goods, including sports equipment and digital cameras, and quantum dots are semiconductor nanocrystals that can act like metals. Quantum dots have been used in a range of medical, scientific, and commercial applications.Generally, there are two ways to create nanomaterials. One is "top-down" and involves converting bulk solids into their nano-sized components. The other is "bottom-up" and entails the self-assembly of atoms to create a nanostructured material.In the lab, scientists use sophisticated tools such as electron microscopes to study nanomaterials and their properties. These instruments can see individual atoms and measure their chemical and physical characteristics. Engineered nanomaterials are being made and used for a wide range of commercial, industrial, and military applications. NIEHS is leading research efforts to understand how these materials affect the environment and human health, leveraging our world class toxicity testing capabilities.FutureA future with nanotechnology could lead to cars that convert more of the energy from gasoline into motion and electricity, and buildings that absorb sunlight to power them. It may also mean faster, more accurate medical tests that provide earlier diagnoses and better therapeutic success rates.It may also mean clearer sunscreens that offer more protection against UV rays, wrinkle- and stain-resistant clothing, and deeper-penetrating therapeutic cosmetics. It might even lead to silver nanoparticles incorporated into bandages that smother and kill harmful bacteria.Engineers who work with nanomaterials manipulate matter at the atomic and molecular level to create new materials that have novel properties. This sounds like a profoundly modern concept, but craftsmen from the premodern eras used similar methods. The Damascans, for example, crafted swords with exceptionally sharp edges and the Romans made iridescent glassware.Venture further to read more…