The automotive sector is a major consumer of material technologies - and nanotechnologies promise to improve the performance of existing technologies significantly. Applications range from already existing - paint quality, fuel cells, batteries, wear-resistant tires, lighter but stronger materials, ultra-thin anti-glare layers for windows and mirrors - to the futuristic - energy-harvesting bodywork, fully self-repairing paint, switchable colors, shape-shifting skin. The basic trends that nanotechnology enables for the automobile are: lighter but stronger materials; improved engine efficiency and fuel consumption for gasoline-powered cars; reduced environmental impact from hydrogen and fuel cell-powered cars; improved and miniaturized electronic systems; and better economies. This article provides an overview of a large number of efforts and applications involving nanotechnologies in the automotive industry.
Nanotechnology shows great potential for revolutionizing the textile industry across its entire range of applications with its ability to impart new functionality to textiles while at the same time maintaining their look and feel. The wool textile industry, for example, is researching the development of textiles with fast-absorbing and quick-drying properties. This has great importance for improving clothing thermophysiological comfort and wearing performance by adjusting the transport of heat and moisture through a fabric which was usually achieved using synthetic fibers. One stubborn hurdle that prevents nanotechnology-enabled 'smart' textiles from becoming more of a commercial reality is the insufficient durability of nanocoatings on textile fibers or the stability of various properties endowed by nanoparticles. Quite simply put, the 'smart' comes off during washing. Developing an effective approach to enhance the coalesce force between nanoparticles and wool fibers has great significance both in scientific and real applications of nanotechnology functionalized textiles.
Quite a lot of nanotechnology research and manufacturing efforts go into synthesizing metal-based nanoparticles. Unfortunately, some of the nanoparticle manufacturing processes themselves as well as the final nanoparticle materials may be of potential concern for environmental regulators and for researchers attempting to address nanomaterial toxicity. As an alternative to using these potentially hazardous metal-based nanoparticles, some researchers are suggesting the use of naturally occurring nanoparticles. However, this area has not yet been well explored with regard to natural nanoparticles' diverse properties and potential applications. Researchers have now made the discovery that naturally occurring nanoparticles have unique optical properties. In addition, they are less toxic and biodegradable than their synthesized, metal-based counterparts. This discovery makes it likely that scientists will be able to find more biocompatible nanoparticles to replace metal-based nanoparticles, predominantly for biomedical applications.
With all the buzz that is being created by portable e-book readers, it's worth taking a look at one of the advanced display technologies - also often referred to as electronic paper - that make these devices happen. Unlike a conventional flat panel display, which uses a power-consuming backlight to illuminate its pixels, electronic paper reflects light like ordinary paper and is capable of holding text and images indefinitely without drawing electricity, while allowing the image to be changed later. Because they can be produced on thin, flexible substrates an due to their paper-like appearance, electrophoretic displays are considered prime examples of the electronic paper category. Electrophoretic displays already are in commercial use, for instance in the Kindle or in the Sony Reader, but so far the displays are mostly black and white. There are still cost and quality issues with color displays. New work by researchers in South Korea shows that organic ink nanoparticles could provide an improved electronic ink fabrication technology resulting in e-paper with high brightness, good contrast ratio, and lower manufacturing cost.
One important aspect of clothing comfort is thermo-physiological comfort. By adjusting the transport of heat and moisture through a fabric, thermo-physiological comfort can keep people comfortable with regard to temperature and moisture. Some hydrophobic fabrics have deficiencies in this area. Take wool. Wool is one of the best insulating fibers known to man - while at the same time being light and soft. The quality that distinguishes wool fibers is the presence of a fatty, water-repellent outer layer that surrounds each fiber. Therefore, the water absorption and sweat venting properties of wool fiber are not very good, which affects the wearing comfort of wool textiles. The wool hydrophobic surface layer is also a barrier to anticrease finishing, dyeing, and grafting of hydrophilic agents, which is an issue in trying to add smart functionalities to wool fabrics.
Researchers have now developed a simple method for fabricating environmentally stable superhydrophilic wool fabrics. They applied silica sols to natural wool fibers to form an ultrathin layer on the surface of the fibers.
OLEDs - organic light-emitting diodes - are full of promise for a range of practical applications. With more efficient and cheaper OLED technologies it becomes possible to make ultraflat, very bright and power-saving OLED televisions, windows that could be used as light source at night, and large-scale organic solar cells. One of the drawbacks of this technology, apart from its currently high manufacturing cost, are problems with the OLED fabrication process where issues such as material damage, yield, and thickness uniformity haven't been completely solved yet. Researchers in Japan have now proposed a nanoparticle-based deposition method that might be able to overcome these fabrication problems.
Most products today are defined as 'nanotechnology product' because they contain nanoparticles in some form or other. For instance, many antimicrobial coatings contain silver in nanoscale form; food products and cosmetics contain nanoparticles; drug formulations are made with nanoscale ingredients; and some products are partially made with composite materials containing nanomaterials (e.g. carbon nanotubes or carbon nanofibers) to mechanically strengthen the material. Two researchers from the Norwegian National Institute for Consumer Research (SIFO), Harald Throne-Holst and Pal Strandbakken, argue that consumer rights in the nanotechnology age are not self-evident but rather have to be strengthened, partly redefined and certainly revived in order to empower and protect consumers.
From an energy savings point of view, the use of smart windows - electrically switchable glass which controls the amount of light passing through when voltage is applied - can save costs for heating, air-conditioning and lighting and avoid the cost of installing and maintaining motorized light screens or blinds or curtains. A disadvantage is of course the fact that the smart windows themselves need to draw energy in order to do their job. Now, researchers have developed a self-powered, fast-switching smart window that doubles as a solar cell, using sun light to power its chromic behavior and making the case for energy savings even more compelling. By employing a patterned tungsten oxide/platinum electrochromic electrode and a dye-sensitized titanium dioxide nanoparticle photoanode, the self-powered photovoltachromic cell (PVCC) which exhibits distinct electrochromic characteristics of a fast switching rate and tunable transmittance under illumination. The novel device has both photoelectrochromic and photovoltaic characteristics.