Curtin University of Technology researchers are a step closer to helping produce cleaner, greener cars using hydrogen fuel cell technology.
Professor Craig Buckley, from Curtin’s Centre for Materials Research, said alternative fuel sources such as hydrogen were becoming increasingly important.
“Oil is a pollutant linked to climate change and is likely to become much more expensive as our supply runs out,” he said.
“We need alternative sources of fuel and for a number of reasons hydrogen is an ideal substitute.
“We can make it from water and it is turned back into water when it is used as a fuel, so it’s much cleaner than petrol.”
The breakthrough that may make hydrogen fuel cell technology a reality for millions of motorists is the use of tiny magnesium nanoparticles to store the hydrogen until it is ready to be used.
Professor Buckley and colleagues Dr Mark Paskevicius and Dr Drew Sheppard have created small magnesium nanoparticles.
“It is easy to bond hydrogen with magnesium and that is one reason why it is a good option as a storage material for hydrogen fuel cells,” Professor Buckley said.
“The problem is getting it back out to actually fuel the engine, because the temperature required to release hydrogen from magnesium is too high for a standard car engine.”
Nanoparticles are one possible way around this, because there have been theoretical calculations that predict that reducing the size of the magnesium particles will reduce the temperature required to release hydrogen.
“In its normal state magnesium needs to be heated to more than 300 degrees Celsius to get the hydrogen back out,” Professor Buckley said.
“By using nanoparticles we may be able to get the required temperature down, taking us one step closer to realistic hydrogen fuel cells for cars.”
To do this, the team used a process called ball-milling to create magnesium nanoparticles seven nanometers in diameter. The nanoparticles are embedded in a salt matrix, which keeps them apart, stopping them from grouping back into larger particles.
“At this small size, the nanoparticles require slightly less heat to release the hydrogen than is required of larger magnesium particles,” Professor Buckley said.
“This result had been predicted theoretically, but has never been proven experimentally before now.”
Using this process, Professor Buckley hopes to create even smaller magnesium nanoparticles.
“The goal is to get them so small that we only need to heat them to 100 degrees Celsius to release hydrogen,” he said.
“This will be tricky, but if we succeed, we will have helped provide a real solution for a low-carbon future.”
The research, ‘Thermodynamic Changes in Mechanochemically Synthesized Magnesium Hydride Nanoparticles’, has been accepted for publication in the prestigious Journal of the American Chemical Society (available online)
