10 Uses for Carbon Nanotubes
By Julian Taub, Tech News Daily, 30 December 2012.
By Julian Taub, Tech News Daily, 30 December 2012.
Carbon nanotubes, miniscule pipes of rolled up carbon atoms, have amazing properties that have taken the world by storm. They are currently being integrated into hundreds of different applications, from green tech to clothing and medicine. Here’s a peak at some uses for this wonder material.
10. Biosensors a.k.a. ‘Nano-noses’
Carbon nanotubes can be modified with protein receptors or DNA that pick up faint traces of chemical. Once the receptor interacts with the chemical, a current surges down the nanotube, identifying the target. It can be used to sniff bombs, search for toxins in the air and water, or be used to test whether someone has skin cancer by checking for a chemical called dimethylsulfone. [More information]
9. Synthetic Muscles
They’re strong, they’re elastic, and they have amazing electrical properties. Researchers have created a carbon nanotube aerogel that expands and contracts as it converts electricity into chemical energy. Carbon nanotubes are suitable for artificial muscles since they retain their shape after being compressed thousands of times, in a similar way that soft tissue does. However, in aerogel form the tubes have an extra property: they grow denser under stress, like weight lifting does to your natural muscles. The nanotube muscle can also operate in extreme environments if need be, which could allow them to be used in space.
8. Gecko Tape
|Image showing gecko clinging to mussel shell. Geckel adhesive combines the wet adhesive properties of mussel adhesive proteins with the dry adhesive strategy of the gecko.|
Geckos climb up smooth surfaces due to the tiny hairs on their feet exploiting the electrostatic force between themselves and the wall. Carbon nanotubes are used in a gecko-inspired tape that sticks to dry smooth surfaces when pressed against them. The tape is amazingly sturdy: Geckos cling on with over 2,000 pounds of force per square foot. The nano-tape quadruples that force. Not only may you be able to climb buildings one day like Spiderman, but you will never have to deal with annoying, sticky tape residue again.
7. Better Displays
From flat screens, to LEDs to flexible displays, nanotubes will increase your viewing pleasure and portability. These tiny pipes of carbon make excellent field emitters or conductive surfaces. They use less energy, are sturdier, and if your machine happens to heat up (which probably won’t happen because they’re amazing heat sinks as well) you’re device won’t even break down. In 2008, Samsung unveiled the first carbon nanotube ‘e-paper’ display, which needs no backlighting. Researchers at the University of Cambridge have also demonstrated a 3D hologram projected by carbon nanotube optical field emitters.
6. Bone Scaffolding
Carbon nanotubes are perfect for allowing damaged bone to restructure itself: they’re strong, lightweight, and can be modified for compatibility with any part of the body. Carbon nanotubes may also help reduce inflammation in broken bone, some studies suggest. Research in Italy last year even used carbon nanotubes to allow the growing back of broken spinal vertebrae in mice.
5. Cell Therapy
Modified carbon nanotubes can enter cells and deliver drugs or knock out unwanted genes. Recently, in a cross-collaboration between researchers in France and England, Alberto Bianco and Kosta Kostarelos used modified nanotubes to control the damage created by a stroke. “We have demonstrated that animals could recover their functions after a stroke thanks to the silencing of a gene following intracranial injection of siRNA complexed to carbon nanotubes,” Bianco said. ”The surprise was the efficacy of the system as we could use a very low amount of carbon nanotubes.” [More information here and here]
Using carbon nanotubes as the electrodes in capacitors provides more current and better electrical and mechanical stability than other leading materials. The surface area of the tubes also gives them an edge: the energy is stored anywhere and everywhere along the tube, not only at the ends, like in a conventional capacitor. Research labs have been working both in Stanford and MIT to create carbon nanotube ultracapacitors that could replace or rival batteries for cars.
3. Improves Efficiency
Carbon nanotubes are added to increase conductivity in films, but it also increases the organization and useable surface area in countless materials, giving them a greater energy gain while protecting against power surges. A tiny addition of nanotubes (about 1 percent of the weight of the entire material) can increase a products efficiency drastically, whether solar cells, plastics, fuel cells or electric generators.
2. Structural Support
Carbon nanotubes have been added to strengthen materials for sports equipment, body armour, vehicles, rockets, and building materials. The nanotube create networks within the composite material to bear the load of the weight and strain placed upon it. However, that’s not all the tube can be used for. The University of Delaware’s Centre for Composite Materials received a grant from the National Science Foundation to research using carbon nanotubes as a ‘smart skin’ to sense changes in a structure’s integrity.
1. Water and Oil Purifiers
Its size, surface area (500 square meter per gram), and adsorption properties make carbon nanotubes an ideal membrane for filtering toxic chemicals, dissolved salts and biological contaminants from water. This technology can help bring clean water and raise the quality of life for millions of people in poorer countries around the world, and also help extract drinking water from the ocean. Seldon Technologies, a Vermont start-up, has created Nanomesh a carbon nanotube filtration system that they are trying to distribute all over the world. The filtration complies with EPA water-drinking standard. It has also been field tested in both Zambia and Bangladesh.
[Source: Tech News Daily. Edited. Top image and some links added.]