A new discovery was made that could improve the energy efficiency of the water electrolysis method of producing hydrogen. A team of researchers from the National University of Singapore (NUS) have made an accidental scientific discovery that could potentially revolutionize the hydrogen economy.
The researchers found that light can trigger a new mechanism in a catalytic material used extensively in water electrolysis where water is broken down into hydrogen and oxygen. The result is a more energy-efficient method of obtaining hydrogen.
The team is led by Associate Professor Xue Jun Min, Dr Wang Xiaopeng and Dr Vincent Lee Wee Siang from the Department of Materials Science and Engineering under the NUS College of Design and Engineering (NUS CDE).
“We discovered that the redox center for electro-catalytic reaction is switched between metal and oxygen, triggered by light… This largely improves the water electrolysis efficiency,” said Associate Professor Xue Jun Min.
An improved water electrolysis efficiency means less energy would be required to produce hydrogen which could potentially make it more widespread and open up new industrial methods of producing the fuel.
The discovery happened three years ago in 2019, when ceiling lights in Assoc Prof Xue’s research lab went off one night due to a power trip. Normally, lights stayed always on. The researchers then found that the performance of a nickel oxyhydroxide-based material in the water electrolysis experiment, which had continued in the dark, had fallen drastically.
“This drop in performance, nobody has ever noticed it before, because no one has ever done the experiment in the dark… Also, the literature says that such a material shouldn’t be sensitive to light; light should not have any effect on its properties,” said Assoc Prof Xue.
The electro-catalytic mechanism in water electrolysis is a very well-researched topic, while the nickel-based material is a very common catalytic material. Therefore, in order to establish that they were on the verge of discovering something groundbreaking, the team had to perform numerous repeated experiments.
They dug deeper into the mechanics behind such a phenomenon and even repeated the experiment outside of Singapore to ensure that their findings were consistent. After three years, the researchers were finally able to share their findings publicly in a paper.
The next step for the team is now working to design a new way to improve industrial processes to generate hydrogen. Assoc Prof Xue is suggesting making the cells containing water to be transparent, so as to introduce light into the water splitting process.
“This should require less energy in the electrolysis process, and it should be much easier using natural light… More hydrogen can be produced in a shorter amount of time, with less energy consumed,” explained Mr Xue.
Improving energy efficiency of the water electrolysis process is one of the main burning issues that is hindering green hydrogen large-scale deployment. Normally, it requires more energy to produce green hydrogen than the energy generated from the hydrogen afterwards when used as a fuel.
Assoc Prof Xue expresses gratitude the findings from his team of researchers could contribute to a scientific discovery. According to him, the way to develop science is not to find new ways to do what has already been done, but to constantly push the boundaries. He also says that only through accumulation of new knowledge, we can improve society progressively.