Researchers from Empa and ETH Zurich have succeeded in producing a prototype of a vibration-damping material that could change the world of mechanics forever. The material of the future is not only able to damp vibrations completely; it can also specifically conduct certain frequencies further.
Transparent conductive films are now an integral part of our everyday lives. Whether in smartphones, tablets, laptops, flat screens or (on a larger scale) in solar cells. Yet they are expensive and complex to manufacture. Now, researchers at Empa have succeeded in developing a method of producing such TCO films, as they are known, that is not only cheaper, but also simpler and more environmentally friendly.
A new, absorbable material from Empa wood research could be of assistance in future oil spill accidents: a chemically modified nanocellulose sponge. The light material absorbs the oil spill, remains floating on the surface and can then be recovered. The absorbent can be produced in an environmentally-friendly manner from recycled paper, wood or agricultural by-products.
Artificial joints have a limited lifespan. After a few years, many hip and knee joints have to be replaced. Much more complex are intervertebral disc implants, which cannot easily be replaced after their "expiry date" and which up to now have had to be reinforced in most cases. This restricts the patient's freedom of movement considerably. Researchers at Empa have now succeeded in coating mobile intervertebral disc implants so that they show no wear and will now last for a lifetime.
All over the world researchers are investigating solar cells which imitate plant photosynthesis, using sunlight and water to create synthetic fuels such as hydrogen. Empa researchers have developed such a photoelectrochemical cell, recreating a moth鈥檚 eye to drastically increase its light collecting efficiency. The cell is made of cheap raw materials 鈥 iron and tungsten oxide.
When the frame of a pair of glasses is bent out of shape, it's not that easy to return it to its original form. If, however, your spectacles are made of a shape memory alloy then you don't have a problem. Just place the frame in hot water and bingo! 鈥 they're as good as new again. Empa researchers have now shown that these materials can also find applications in the building industry. For example in the reinforcement of bridges.
The antibacterial properties of silver-coated textiles are popular in the fields of sport and medicine. A team at Empa has now investigated how different silver coatings behave in the washing machine, and they have discovered something important: textiles with nano-coatings release fewer nano-particles into the washing water than those with normal coatings.
For the first time, researchers at Empa and the Max Planck Institute for Solid State Research have succeeded in "growing" single-wall carbon nanotubes (CNT) with a single predefined structure - and hence with identical electronic properties. And here is how they pulled it off: the CNTs "assembled themselves", as it were, out of tailor-made organic precursor molecules on a platinum surface, as reported by the researchers in the latest issue of the journal "Nature". In future, CNTs of this kind may be used in ultra-sensitive light detectors and ultra-small transistors.
Graphene is a semiconductor when prepared as an ultra-narrow ribbon 鈥 although the material is actually a conductive material. Researchers from Empa and the Max Planck Institute for Polymer Research have now developed a new method to selectively dope graphene molecules with nitrogen atoms. By seamlessly stringing together doped and undoped graphene pieces, they were able to form 鈥漢eterojunctions鈥 in the nanoribbons, thereby fulfilling a basic requirement for electronic current to flow in only one direction when voltage is applied 鈥 the first step towards a graphene transistor. Furthermore, the team has successfully managed to remove graphene nanoribbons from the gold substrate on which they were grown and to transfer them onto a non-conductive material.
The production and consumption of chemical substances threatening the ozone layer has been regulated since 1987 in the Montreal Protocol. Eight international expert reports have since been published, which examine the current situation and the future of the threat to the ozone layer. Empa scientists made a decisive contribution to the latest report 鈥 presented on 10 September at the United Nations Headquarters in New York.