A new method of extracting hydrogen from water more efficiently could help to ‘underpin the capture’ of renewable energy in the form of sustainable fuel, scientists say.
In a paper published recently in the journal Nature Communications, researchers from universities in the UK, Portugal, Germany and Hungary describe how pulsing electric current through a layered catalyst has allowed them to almost double the amount of hydrogen produced per millivolt of electricity used during the electrolysis process, which breaks the bonds between the hydrogen and oxygen atoms of water, releasing hydrogen and oxygen gas.
If the electric current for the process is generated through renewable means such as wind or solar power, the entire process releases no additional carbon into the atmosphere.
The hydrogen gas can then be used as a zero-emission fuel source in some forms of transport — or for heating homes.
The team’s research focused on finding a more efficient way to produce hydrogen through the electrocatalytic water splitting reaction. They discovered that electrodes covered with a molybdenum telluride catalyst produced more hydrogen when a specific pattern of high-current pulses was applied.
By optimising the pulses of current through the acidic electrolyte, they have been able to reduce the amount of energy needed to make a given amount of hydrogen by nearly 50%.
Alexey Ganin, who directed the research team (www.gla.ac.uk
), said: “The UK currently meets about a third of its energy production needs through renewable sources, while the figure for Scotland is about 80%.
"Experts predict that we’ll soon reach a point where we’ll be producing more renewable electricity than our consumption demands. Currently, however, the excess energy must be used as it’s produced, or else it goes to waste.
"It’s vital that we develop a robust suite of methods to store the energy for later use. Batteries are one way to do that, but hydrogen is a very promising alternative.
"Our research provides an important new insight into producing hydrogen from electrolysis more effectively and more economically, and we’re keen to pursue this promising avenue of investigation.”