Rensselaer Pioneers Hydrogen Storage and Graphene Composites
Groundbreaking research currently being conducted at Rensselaer Polytechnic Institute is helping to contribute toward energy efficiency and the growth of the hydrogen-powered vehicle, a leading candidate for green cars. Recently, the Nanostructured Materials and Devices Lab at Rensselaer has been focusing their research on graphene, a two-dimensional carbon-based sheet capable of storing hydrogen at levels far exceeding that of any other material currently available. Graphene’s main component – graphite – is available at a cost low enough to allow bulk manufacturing, and its potential for use in hydrogen vehicles and many other polymer composite products is promising. Current Research
For hydrogen-powered vehicles to replace the conventional oil- and gas-powered ones, four major challenges must be addressed – distribution, production, energy conversion and storage. The specialized research team within Rensselaer’s Department of Mechanical, Aerospace and Nuclear Engineering
is addressing the challenge of storage; their tests with graphene have found a storage capacity of 14% by weight at room temperature, far surpassing the Department of Energy’s goal of 9% capacity by 2015. This means that engineered graphene can store, absorb and release more hydrogen molecules at a lower cost and higher efficiency than ever before.
Graphene is called the strongest and thinnest of materials, with a density of more than six times that of copper. It is a layer of carbon one atom thick; it is mass-producible; and because it is carbon-based, it is available in abundance. Rensselaer’s work on graphene enhancement sought to strengthen materials to which the carbon-based material could be added, such as composites, and their results show an improved resistance to fatigue crack propagation.
The Rensselaer team discovered three advantages of graphene that ensure its future in several electrical and mechanical processes. First, its rough and wrinkled surface texture enhances its ability to interlock with surrounding polymer materials, giving strength to an infused composite. Secondly, compared to carbon nanotubes, graphene planar sheets offer a considerably higher surface area to be in contact with a polymer composite, further enhancing its strength. And lastly, small, micro-cracks in a composite structure can be deflected by the two-dimensional graphene sheet surrounding it, absorbing energy that could otherwise lead to breaks and cracks.Future Developments
The research team is hopeful that advanced composites infused with graphene can become an integral component in new windmill blades and aircraft, as well as several other applications with similar lightweight demands. Javad Rafiee, a Ph.D. candidate in mechanical engineering, is focusing his research on applying graphene sheets to the inside of hydrogen storage tanks for next-generation automobiles. Cheap yet strong, graphene is beginning to make its way into commercial applications and transition from the lab to the marketplace. Future plans at Rensselaer include partnering with private business. Once Rafiee finishes his graduate research, he hopes to start a business focused on clean energy and green manufacturing. Team
Nikhil Koratkar, professor in the Department of Mechanical, Aerospace and Nuclear Engineering, heads Rensselaer’s Nanostructured Materials and Devices lab. Mechanical engineering Ph.D. candidate Javad Rafiee is one of the leading researchers on the team and recently was awarded a $30,000 Lemelson-MIT Rensselaer Student Prize for his work with hydrogen storage tanks and graphene. Mechanical engineering Ph.D. candidate Mohammad Ali Rafiee, Javad’s brother, is another leading researcher on the team and was recently awarded the 2010 International Robert L. Lichten Award from American Helicopter Society (AHS) for his breakthrough in graphene nanocomposites for the aerospace industry. Contact
Nikhil Koratkar, Professor
Mechanical, Aerospace, and Nuclear Engineering
Jonsson Engineering Center
110 8th Street
Troy, New York 12180
Phone: (518) 276-2630