Carbon Nanotube and Metal Nanowire Actuators
It is well known that carbon nanotubes and arrays of metal nanowires are ultra-strong. What is less well known is that voltage can be applied to make these materials contract and expand, creating impressive muscle like actuation. We are studying this new method of actuation and its initial applications.
Carbon nanotubes have attracted extensive attention in the past few years because of their appealing mechanical and electronic properties. They not only have some of the highest tensile strengths among all materials and very high Young's moduli, but also can be metallic or semiconducting depending on their geometry. Numerous applications have been suggested for them in electronics, mechanical engineering and material science, many of which require macroscopic combinations of these nanoscopic tubes. Many attempts have been made in making macroscopic structures of nanotubes that preserve the desirable mechanical and electronic properties of the individual tubes. The focus of this research is the study of actuation in materials made from Carbon nanotube yarns and similar structures made from metal nanowires. The yarns are spun from hundreds of thousands of well-aligned nanotubes by our collaborators in the Nanotech institute of UTD and exhibit some of the best mechanical properties among macroscopic structures made of nanotubes. The yarns show great potential for applications as they are strong and easy to use. The metal nanowires are formed by creating tens of thousand of centimeter long nanowires in parallel, and actuating by applying voltage through an electrolyte. Both these forms of actuators promise to achieve exception and perhaps unprecedented mechanical performance.