New type of catalyst could aid hydrogen fuel

Ferroelectric substances might offer the right combination of catch and release

SPLIT UP Hydrogen, a clean-burning fuel, can be extracted from water molecules by splitting oxygen atoms from the hydrogens. A new computer simulation suggests a strategy for catalyzing that reaction that has the potential to be more efficient than current methods.

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By Tom Siegfried

March 21, 2016 at 1:46 pm

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 therefore should be able to design a cycle of states that extracts hydrogen efficiently, Kakekhani reported March 17 in a news conference at a meeting of the American Physical Society.

“It’s a conceptual study that should be experimentally confirmed,” he said. A report on the work was also published online March 8 in the Journal of Materials Chemistry A.