Nanotechnologies (technologies based on particles of billionth of a meter in dimension) will be a driving force behind a new industrial revolution. Both private and public-sector spending are consistently increasing. Nanotechnologies will be a major technological force for change across all industrial sectors in the foreseeable future and are likely to deliver substantial growth opportunities. The size of the market for nanotechnology products is already comparable to other high-tech sectors, while the expected growth rates over the next few years will be even higher.
Nanotechnology describes technologies applied on a nanometer scale with widespread applications in numerous industries. Nanotechnology encompasses the production and application of physical, chemical, and biological systems at scales ranging from individual atoms or molecules to around 100 nanometers, as well as the integration of the resulting nanostructures into larger systems.
The term ”nanotechnology” was created by Norio Taniguchi of Tokyo University in 1974 to describe the precision manufacture of materials with nanometer tolerances; the nomenclature’s origins date back to Richard Feynman’s talk ”There’s Plenty of Room at the Bottom”,(1959) in which he proposed the direct manipulation of individual atoms as a more powerful form of synthetic chemistry. Eric Drexler of MIT expanded Taniguchi’s definition and popularized nanotechnology in his 1986 book ”Engines of Creation: The Coming Era of Nanotechnology”.
Because of their large surface-area-to-mass ratio, nanoparticles can become more chemically reactive and enhance their chemical and physical properties. In addition, below the 50 nm scale quantum effects predominate, creating different physical interactions.
Nanoparticles have long existed in nature: sea salt and volcanic ash can be found in the atmosphere in the form of nanoparticles. With modern processing techniques, it is possible to turn many common bulk materials (such as TiO2) into nanoparticles. Engineers can capture some of those properties by mating nanoparticles into more common materials.
Modern industrial nanotechnology had its origins in the 1930s, in processes used to create silver coatings for photographic film. The earliest known use of nanoparticles is in the 800’s CE in the Mid-East. Arab potters used nanoparticles in their glazes so that objects would change color depending on the viewing angle.
Nanoscale materials have been used in the past in numerous applications: window glass, sunglasses, car bumpers, and paints. Today, advances in technology are leading to applications in materials manufacturing, computer chips, medical diagnosis and health care, energy, biotechnology, space exploration, etc. Nanotechnology is expected to have a significant impact on the world economy and society within the next 10 to 15 years, growing in importance as further scientific and technology breakthroughs are achieved.
Nano-particles can be created in three ways:
1. The traditional “sol-gel” approach, which creates a “commodity” nanoparticle. The Sol-gel process became main process for TiO2 nanoparticles because of its low reaction temperature, high particle distribution, particle-size controllable. TiO2 sol is prepared with Butyl titanate as the precursor, ethanol as solvent and hydrochloric acid as the catalyst. Nowadays, a common variation of the sol-gel method for obtaining TiO2 nanoparticles involves the use of organic solution at low temperatures.
2. The “supercritical water” technology, which creates customizable nanoparticles of narrow ranges. Hydrothermal synthesis is generally defined as crystal synthesis or crystal growth under high temperature and high pressure water conditions from substances which are insoluble in ordinary temperature and pressure (<100 °C, <1 atm). Hydrothermal synthesis is usually carried out below 300 °C. The critical temperature and pressure of water are 374 °C and 22.1 MPa, respectively.
3. The “wall-free” method, which is an improvement of (2), preventing material build-up on the reactor wall leading to shut-downs.
Of particular interest are those nanoparticles derived from ferrous and non-ferrous metals: Copper/Copper alloys, Nickel/Nickel alloys, Zinc/Zinc alloys, Cobalt/Cobalt alloys, etc. TiO2 nanoparticles demonstrate valuable properties in photo catalysis as well.
Potential applications are:
· Metal nanoparticles, in particular silver, in antibacterial applications.
· Magnetic iron based alloys – reduced loses in energy transmission.
· Structural applications: light metals with superior mechanical properties: Al and Mg alloys, Ti and Ti alloys.
· Coatings – higher wear resistance, less friction, better corrosion resistance, sustainable production process, etc.
· Mg and its alloys as a material for hydrogen storage.
· Nano-powders, mainly of noble metals as well as aluminium: these result in a high material activity, which could be used as catalysts.
Other possible uses are:
· Sunglasses using protective and antireflective ultrathin polymer coatings.
· Textiles can incorporate nanotechnology to make practical improvements to such properties as wind proofing and waterproofing, preventing wrinkling or staining, and guarding against electrostatic discharges.
· Clothes with additional electronic functionalities, so-called ”smart clothes” or ”wearable electronics”.
· High Performance sports equipment: high-performance ski waxes, tennis rackets with carbon nanotubes for increased torsion and flex resistance.
· Sunscreens and cosmetics based on nanotech. Customers favor products that are translucent because they suggest purity.
· Televisions using carbon nanotubes, which, would consume less energy than plasma or liquid crystal display (LCD) sets.
JTS – 1/12/2018