Madison – A team of researchers at the Lab of Song Jin, a professor of chemistry at the University of Wisconsin-Madison (UW-Madison), discovered a highly efficient catalyst that eases the way to a future ‘hydrogen economy.’ This new finding works with water supply and there is no climate-altering carbon dioxide involved. The research was published in the online edition of Nature Materials yesterday.

How did they do it?

Jin’s team separate water into hydrogen and oxygen using a catalyst made of the abundant elements cobalt, phosphorus and sulfur. Due to the fact that previously Hydrogen was produced by separating water with electrical power, this new way of doing it could also be use to store more energy.

A hydrogen filling station in Reykjavík. Iceland provides an ideal location to test the viability of hydrogen as a fuel source for the future, since it is a small country of only 320,000 people, with over 60% living in the capital, Reykjavík. The relatively small scale of the infrastructure will make it easier to transition the country from oil to hydrogen. Credits: Wikipedia

However, not everything is as perfect as it seems, despite the fact that water supply is basically infinite, a possible obstacle to a future “Hydrogen economy” could be that both platinum and noble metals such as platinum, palladium, iridium and gold which are needed for the water-splitting process, are usually very expensive.

“In the hydrogen evolution reaction, the whole game is coming up with inexpensive alternatives to platinum and the other noble metals,” says Song Jin

On Jin’s paper work, he and the team suggested a hydrogen-making catalyst that contains phosphorus, sulfur and cobalt, instead of platinum which is 1,000 times more expensive.

Catalysts is a substance which speeds up a reaction, but is chemically unchanged at the end of the reaction, is almost as efficient as platinum and so far it has the highest catalytic fulfillment compared to others non-noble metal catalysts, as the team suggests.

The discovery

Miguel Cabán-Acevedo and Michael Stone, both Jin’s students, were the responsibles for this discovery. They replaced iron to make cobalt pyrite and then added phosphorus, getting the impressive high-performance catalyst. And to make it even more energy-saver, Jin is aiming to use the sunlight to split the water directly instead of electricity which is the common energy source for this action.

On a press release delivered by the UW-Madison, Jin said: “We have demonstrated a proof of concept device for using this cobalt catalyst and solar energy to drive hydrogen generation, which also has the best reported efficiency for systems that rely only on inexpensive catalysts and materials to convert directly from sunlight to hydrogen.”

What’s coming next?

UW stated that many questions have emerged since this form of catalyst has only been tested in Jin’s lab. “One needs to consider the cost of the catalyst compared to the whole system. There is always a tradeoff: If you want to build the best electrolyzer, you still want to use platinum. If you are able to sacrifice a bit of performance and are more concerned about the cost and scalability, you may use this new cobalt catalyst.”

Source: University of Wisconsin-Madison