Nanotechnology Innovations Advance Electronics, Materials, and Manufacturing
- Tuesday, 01 June 2010
WANDA’s liquid-handling robotics prepare and initiate reactions by injecting nanocrystal precursor chemicals into an array of reactors. After a series of reactions is complete, the structural and optical properties of these nanocrystals can be screened rapidly, also using automated methods. WANDA is housed inside a nitrogen-filled chamber designed to keep oxygen and water from interacting with reactive precursor chemicals and freshly formed nanocrystals. Since the robot is controlled by software protocols, novice users can direct WANDA to perform complex workflows that traditionally require extensive chemistry experience.
WANDA has produced nanomaterials under conditions analogous to those used in traditional flask-based chemistry. Starting with nanomaterials such as cadmium selenide quantum dots, whose size can be adjusted to emit different colors of visible light, the team showed how WANDA can optimize the size, crystal structure, and luminescence properties of different nanocrystals.
“This technology will change the way nanoscience research is performed,” said Emory Chan, a senior scientific engineering associate at the Molecular Foundry. “Not only does WANDA enable the optimization and mass production of nanoparticles our users need, but this robot also facilitates experiments that give us a deeper understanding into the chemistry and physics of nanoscale materials.”
Nano-Based Technology to Replace Semiconductors
Nano-based technology created by Dr. Koby Scheuer of Tel Aviv University’s School of Electrical Engineering may make computers and the Internet hundreds of times faster — a communications technology enabler that could be in use in as little as five or ten years from now. The plastic-based technology is designed for the nanophotonics market for optical devices and components. The plastic-based “filter” is made from nanometer-sized grooves embedded into the plastic. When used in fiber-optic cable switches, the device will make communication devices smaller, more flexible, and more powerful.
Every optical device used in today’s communication tools has a filter. Whether it’s the drive reader in a laptop or the cable that brings long-distance phone calls, each system uses filters to clean up the signal and interpret different messages. In the next decade, fiber-optic cables that now run from city to city will feed directly into each individual home. When that technology comes to light, the new plastic-based switches could revolutionize communications.
The new filter uses a plastic-based switch, replacing hard-to-fabricate and expensive semiconductors, which can take days or months to manufacture. The plastic polymer switches come in a liquid solution. Using a method called “stamping,” almost any lab can make optical devices out of the silicon rubber mold, which is scored with nano-sized grooves, invisible to the eye and each less than a millionth of a meter in width. A plastic solution can be poured over the mold to replicate the optical switch in minutes. When in place in a fiber-optic network, the grooves on the switch modulate light coming in through the cables, and the data is filtered and encoded into usable information.
The device can also be used in airplane, ship, and rocket gyros; inserted into cell phones; and made a part of flexible virtual reality gloves so doctors can “operate” on computer networks over large distances.
Making the Common T-Shirt a Super-Textile
A simple cotton T-shirt may one day be converted into tougher, more comfortable body armor for soldiers or police officers thanks to a development by researchers at the University of South Carolina. They have increased the toughness of a T-shirt by combining the carbon in the shirt’s cotton with boron. The result is a lightweight shirt reinforced with boron carbide, the same material used to protect tanks.
The scientists started with plain, white T-shirts that were cut into thin strips and dipped into a boron solution. The strips were later removed from the solution and heated in an oven. The heat changes the cotton fibers into carbon fibers, which react with the boron solution and produce boron carbide. The result is a fabric that’s lightweight, tougher and stiffer than the original T-shirt, yet flexible enough that it can be bent. That flexibility is an improvement over the heavy boron-carbide plates used in bulletproof vests and body armor.
The boron-carbide bulk material currently in use is brittle. In contrast, the boron-carbide nanowires synthesized by the scientists keep the same strength and stiffness of the bulk boron carbide, but have super-elasticity. Much tougher body armors could be fabricated using this new technique. It could also be used to produce lightweight, fuel-efficient cars and aircraft. The resulting boron-carbide fabric can also block almost all ultraviolet rays.