Prof Mike Lyons, School of Chemistry at Trinity College Dublin
Prof Mike Lyons from the School of Chemistry at Trinity College Dublin (TCD) likens his research team’s new method of splitting water into hydrogen and oxygen to an octopus, whose arms reach out in different directions. His point is that the fundamental science he is carrying out has ‘arms’ – spin-offs that cross over into other areas, such as sensor technologies, with commercial applications.
Just recently, Lyons and his research group at the nanoscience institute CRANN [Centre for Research on Adaptive Nanostructures and Nanodevices] at TCD announced they had found a new way of splitting water into its components hydrogen and oxygen – a method known as water electrolysis – based on iron and nickel oxide.
Describing the research breakthrough as a “world first”, Lyons and his team believe their methods are the first inexpensive and efficient methods of water electrolysis to be identified worldwide.
According to Lyons, his research, which has leveraged €800,000 in funding via Science Foundation Ireland (SFI), has the potential to have a commercial impact so industry can capitalise on the research in the near future.
Lyons is professor of physical chemistry at TCD, while he is also a SFI principal investigator (PI) in the School of Chemistry and at the SFI-funded CRANN. He has been teaching at TCD since 1984.
With his research team, Lyons is working on a new way to carry out water electrolysis more sustainably and, ultimately, use less energy.
Costly process
While water electrolysis has been around for some time, the raw materials used for the process are expensive. The best methods of water electrolysis available to date are comprised of a lot more costly materials, such as ruthenium and iridium, said Lyons.
If you compare the costs, he said these materials might be $600 per gram, whereas nickel is a “far, far lower fraction” of the cost.
In industry, Lyons said this CRANN research is going to be important for large-scale water electrolysis because one expensive material is being substituted for a far more common, inexpensive one.
“This will have large-scale industrial implications,” he said.
Describing how water electrolysis has been a “textbook technology” that kids are taught in school science labs, Lyons said it goes as far back as the heyday of Michael Faraday, the British inventor.
Fast-forward to today, where various types of electrolysis cells are used in industry.
“Our premise is improving the materials,” Lyons said. Firstly, it’s about making the materials that conduct electromagnetic currents more inexpensively.
“It’s the materials that are key,” said Lyons. “If you can cut down on the total amount of electrical energy that you have to input to generate the two gases [hydrogen and oxygen] then it becomes cheaper for industry to do.”
Lyons said the team believes this research will have a “significant” impact in the worldwide race to cheaply and efficiently produce hydrogen gas that can be used across industry – for instance, in sensor technologies and to help green the transport sector.
“One of the big problems nowadays is that a lot of the noble metals come from regions in the world that are perhaps not the most politically stable. One of the most common ones is platinum, which is very expensive.”
Platinum is used in a lot of electrochemical applications, he said, such as fuel cells for transport.
“One of the big advancements perhaps over the last 30 or 40 years since the Apollo space mission in the Seventies is the amount of platinum that’s now required to reduce oxygen to water in fuel cells.”
In terms of fuel cells in cars, hydrogen is one fuel and oxygen from the air is another fuel. Water electrolysis produces the type of purity of hydrogen required for the fuel cell in a car, he said.
“From the oxygen point of view it is very, very difficult to reduce and people have been using platinum. It’s an expensive material so you need to be able to cut down on it.”
Alternative materials
In an effort to depart from platinum, scientists started using materials such as ruthenium and iridium for water electrolysis.
The TCD team has been researching the use of nickel, cobalt and iron oxide in water electrolysis.
“We’ve also been trying strategies of getting the more standard noble metals – because they are good – and mixing them with inexpensive ones, while simultaneously trying to keep their activity of splitting the water or reducing the oxygen.”
In the case of a fuel cell, scientists are putting the oxygen and hydrogen in to generate electricity from the chemicals.
“If the reactions at the two electrodes are inefficient and need a lot of energy input, the voltage output will be lower, so it won’t be as efficient,” said Lyons.
“If we can develop materials that can minimise that voltage loss we can make the whole process occur a lot more readily. That’s where the fundamental science comes in,” he said.
In order to optimise the technologies, the fundamentals need to be understood. It was that understanding that led Lyons and his team to these materials.
Other applications
Lyons’ research could have other impacts on industry, as well.
“Along the way we discovered that these metal oxide materials had other beneficial uses. That’s the knock-on effect from scientific research. Some of these research discoveries can have a commercial spin-off.
“We are at the moment using these metal oxides as electrochemical sensors for materials like glucose.”
In the management of diabetes, for instance, a blood-glucose sensor is available on the market.
“It’s a multi-billion-euro industry every year, but such glucose sensors use enzymes, which are biological catalysts,” said Lyons.
Describing enzymes as “temperamental creatures” he said the researchers at CRANN are trying to utilise enzyme mimics based on these metal oxides.
“They will also react and detect glucose levels. There would be industrial interest there.”
A version of this article appeared in the Sunday Times on 21 July
