In the search for alternatives to gasoline, many are considering the potential of fuel cells. Dr. Piotr Zelenay gave a Materials Research Seminar on his work in improving fuel cells.
In his talk entitled “High Performance Non-precious Metal Catalysts for Oxygen Reduction in Fuel Cells,” Zelenay described his research at Los Alamos National Laboratory as the director of their fuel cell research project. “This is work we’ve been performing for four or five years now, funded by the Office of Energy Efficiency Department of the DOE,” said Zelenay.
Their goal is to find cheaper metals to replace platinum, which is widely used for the electrode catalyst. Zelenay described the problems with platinum, “We are looking at a commodity that has high cost, high price volatility, and is available in two or maybe three places in the world.”
Zelenay said, “The fuel cell stack represents almost 50% of the overall cost. Then when we break down the cost of the stack components, we notice that the electrode, which is the catalyst itself, represents more than 50% of the stack cost.”
The team from Los Alamos National Laboratory found that catalysts synthesized from iron gives stability in the fuel cell performance. So the fuel cell runs well over the long-term. But the challenge in finding a catalyst from a non-precious metal is achieving an oxygen reduction activity high enough for the DOE’s standards. Zelenay found, “Only when we added transition elements to the synthesis were we able to move the activity to where we wanted it to be.” The metal the team selected was cobalt. The research process is still on going, but Zelenay’s team found a mixture of a catalyst synthesized from iron and cobalt that shows both stability and high activity.
Universities and laboratories have long been interested in finding new catalysts. Zelenay said, “Not surprisingly, non-precious metal oxygen reduction catalysts have been looked at with great interest for quite a few decades by now.” Before this project, researchers have tried many different methods of synthesizing catalysts.
Los Alamos National Laboratory has previously done work with non-precious metals, but at low temperatures. “The problem was, despite our efforts, we were unable to increase activity of the cobalt poly pyrrole. And we decided to move away from low temperature catalysts and move to the high temperature approach,” said Zelenay.
In order for fuel cells to have a chance at practical use, they must first be much more affordable. Zelenay emphasized that the cost “needs to addressed, especially for fuel cell systems for higher power applications, such as automobiles.”