Ferroelectric substances might offer the right combination of catch and release
BALTIMORE — For a long time now, hydrogen has been the fuel of the future. A new idea for extracting hydrogen from water might help that future arrive a little sooner.
Today, producing hydrogen requires burning fossil fuels or using water-splitting catalysts that work relatively inefficiently, says physicist Arvin Kakekhani of Yale University. But Kakekhani and Sohrab Ismail-Beigi, also at Yale, identified a strategy using materials known as ferroelectric oxides to catalytically separate hydrogen from oxygen more effectively.
Catalysis requires a surface that both grips a water molecule in order to split it and releases the hydrogen atoms separated in the process. Ordinary catalysts must compromise between these two competing qualities. But a ferroelectric substance such as lead titanate can be prepared so that heat can switch it from a state suitable for splitting to another state good at releasing, computer simulations showed. Researchers