Improving Solid Oxide Fuel Cells
Solid-oxide fuel cells work by electrochemically oxidizing a fuel to transform chemical energy into electricity. However, high operating temperatures required for oxygen ion conductivity is inhibiting its use in vehicle applications. What's more, there are slow start-up and shut-down times, limited fuel cell lifespan and costly components are necessary for the cell housing. Joshua Hertz, University of Delaware (udel.edu) assistant professor in the department of mechanical engineering, is researching a solution. He's creating electrolytes from thin layers of materials in order to strain atomic lattices. The idea behind this is that it will improve oxygen ion conductivity, thereby allowing operation at lower temperatures. Hertz's research is ongoing, but his early findings show that some of the electrolytes ease ion movement in solids. "Here we will perform a very systematic study to fundamentally understand how we can use these effects to improve the mobility of oxygen ions," he says.
Open Wide for Lighter Vehicles
Where does the secret to lighter, more fuel-efficient vehicles lie? Accord-ing to Queensland University of Technology (QUT; qut.edu.au) physics researcher John Barry, the answer might be in your mouth. "Teeth in different animals have been adapted or 'engineered' for various purposes," he explains. "As engineering materials, teeth are composite materials with properties which are much superior to any existing synthetic composite."
Barry's research has involved the lungfish, or salamander, and garfish. The former is an ancient species with a complex tooth microstructure, while the latter has very durable teeth. He says that studying and copying structures in teeth could lead to the creation of new lines of light weight composites for the automotive and aerospace industries.
Protecting the Platinum (in Fuel Cells)
One of the inhibitors to the proliferation of fuel cells is platinum. That's right: the element that is more common to Tiffany's than to an engine plant. This material acts as a catalyst in fuel cells. And not only is it expensive, but it tends to wear. In fact, it actually dissolves during use. So researchers from the U.S. Department of Energy (DOE) Brookhaven National Laboratory (bnl.gov) have come up with a solution. They've developed a new electrocatalyst for fuel cells that uses less platinum and are more wear resistant.
The catalyst developed by the DOE is composed of a thin, single layer of platinum over a palladium nano particle core. The core protects the surrounding platinum, allowing it to maintain reactivity for a longer period of time, says lead researcher Radoslav Adzic. And researchers have proof of concept: They put the catalyst through 100,000 cycles and found minimal wear on the platinum.