26 March 2013

Meganne Christian in the lab

Image courtesy: Maganne Christian, University of New South Wales

 

Imagine being able to convert your organic waste into hydrogen and then use it to power your car or household appliances, independently of the electricity grid—such a thought may soon be turned into reality thanks to ground breaking research funded by the ARC.

The application of hydrogen as an alternative fuel source hinges on the practicality of its storage. Borohydrides (including lithium and sodium compounds) are effective storage materials, but it was believed that once the energy was released it could not be reabsorbed—a critical limitation. 

However, recent results published in the journal ACS Nano by Dr Kondo-Francois Aguey-Zinsou from the School of Chemical Engineering at The University of New South Wales (UNSW), demonstrate for the first time that reversibility is indeed possible using a borohydride material by itself.

“No one has ever tried to combine such a nanoscale approach before because they thought it was too difficult, and couldn’t be done,” Dr Aguey-Zinsou said.

“We are the first to do so, and demonstrate that energy in the form of hydrogen can be stored with sodium borohydride at practical temperatures and pressures.”

The researchers also observed remarkable improvements in the thermodynamic and kinetic properties of the material. This means the chemical reactions needed to absorb and release hydrogen occurred faster than previously studied materials, and at significantly reduced temperatures.

“By controlling the way the atoms are organised we can tune their properties and make them reversible—this means they can release and reabsorb hydrogen.

“We now have a way to tap into all these borohydride materials, which is particularly exciting for application in vehicles because of their high hydrogen storage capacity,” Dr Aguey-Zinsou said.

“In future generations all of the current resources we require to generate fuel will be gone, it is for this reason that discovering an alternative energy carrier is imperative. By the end of the century, Hydrogen will be the versatile fuel that we generate from a multitude of renewable resources. On a domestic level, you will be able to convert your organic waste into hydrogen, for example.”

“With the materials and technology we have developed, the hydrogen that you generate could be stored indefinitely and utilised when needed to power your car, appliances and electronics—independent of the grid, completely clean, renewable, and free from CDI emissions.”

“The key thing here is that we’ve opened the doorway,” Dr Aguey-Zinsou said.

The research is funded through the Australian Research Council Discovery Projects scheme and supported by the Australian Research Council Linkage Infrastructure Equipment Facilities scheme.

For more information on this article please email Dr Kondo-Francois Aguey-Zinsou, School of Chemical Engineering, UNSW.

A presentation of this research is also available on Youtube.