They scrutinised a naturally-occurring enzyme named ‘hydrogenase’ that has evolved an astonishing ability to deconstruct hydrogen, mimicking the reaction that takes place in a platinum fuel cell. However, it does this using common metals and at room temperature.
With the help of intense synchrotron light, the group from the Universities of Oxford and Dundee and the Research Complex at Harwell were able to pinpoint individual atoms inside hydrogenase that are involved in the hydrogen conversion process, thus unravelling the mystery of how it works.
They discovered that the enzyme uses a reaction between two very common elements: nickel and iron, and a single nitrogen atom.
Project leader, Professor Simon Phillips, explains the complex atomic reactions behind the hydrogenase conversion process: “The nickel and iron atoms are strongly drawn to the nitrogen atom and want to join with it, but the molecular make up of hydrogenase keeps them apart.
“This creates a strong pull between the metals and the nitrogen atom, and if a hydrogen molecule gets caught between them, it gets torn apart into two individual hydrogen atoms. This generates a flow of electricity – just like in manmade fuel cells”.
Now that we know the exact combination of atoms involved in this process, scientists can look at replacing the expensive platinum currently used in hydrogen fuel cells and switch to affordable and abundant nickel and iron. This would make the production of energy from hydrogen easier and cheaper than ever before.
The next stage will be for the group to try and observe the hydrogenase converting hydrogen in real time – like a molecular movie. With more research on the behaviour and capabilities of hydrogenase, it may eventually be possible to harness the enzyme’s power to support hydrogen energy production on a wider scale.
There’s still a way to go before we have a truly viable hydrogen economy. Issues with hydrogen production, storage and conversion all need to be addressed before it can become a widespread source of renewable energy. But thanks to the work of scientists around the globe, we are pushing forwards.
There is no doubt that we can create a greener planet, but we must consider even the tiniest components of matter, for it is these sub-microscopic particles that govern the fundamental processes taking place all around us.
So let’s not underestimate the humble hydrogen molecule: hundreds of thousands of times smaller than the width of a human hair, and yet poised to reshape the world.
A brighter light for science
