Professor Leone Spiccia of the Monash School of Chemistry, who is a lead researcher in the water splitting program, told iTWire that the MIT and Monash programs are two independent approaches to the same problem.
"The MIT one focusses on a Cobalt Phosphate material that they can make and deposit and then they use that to oxidise water. In our case we use a Manganese cubic structure which was developed initially by collaborator (Professor) Chuck Dismukes (of Princeton) as a mimick of the Managanese cluster that's found in all photosynthetic organisms," says Professor Spiccia.
"That is the only centre in nature that actually oxidises water. That's the big difference. A manganese cluster is central to a plant's ability to use water, carbon dioxide and sunlight to make carbohydrates and oxygen. We've taken what Chuck Dismukes has done a step further, harnessing the ability of these molecules to convert water into its component elements, oxygen and hydrogen," Professor Spiccia said.
"A company in the UK is using a dual cell approach where you generate electricity with a solar cell and you use that electricity to split water. Our approach is that you do away with the solar cell altogether and just irradiate one device and generate hydrogen and oxygen in the process."
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Perhaps one of the most tantalising aspects of the new technology is that unlike photovoltaic cells, the photosynthesis replication process being reproduced at Monash requires relatively low levels of sunlight.
"The other thing we've actually shown is that we can just use sea water and the device will operate very well. If you can use ocean water directly by just simply filtering it without having to use clean water it's a big advantage."
According Professor Spiccia the successful production of Hydrogen in the laboratory using the replicated photosynthetic process is the result of 10 years research.
"The work was started about 10 years ago at Princeton and what they showed was that if you irradiated these clusters with light you could actually kick out one molecule of Oxygen. The breakthrough we've come up between the three groups (Monash, Princeton and CSIRO) is to get the cubane to turn over - to release one molecule of Oxygen, then take up water and then release some more Oxygen.
"To do that, we used a Nafion polymer membrane which is actually used in fuel cells as a photon conductor. And so we can poke the cubanes into that film and once you shine light on it and apply a bias, the device will work for three days without too much trouble."
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Commercialisation of the process, however, is still around the 2020 time frame, according to Professor Spiccia.
"To be realistic you need a 15 year time frame before something can actually make it into the commercial process."
Professor Spiccia said the efficiency of the system needed to be improved, but this breakthrough had huge potential. "We need to continue to learn from nature so that we can better master this process."
"Hydrogen has long been considered the ideal clean green fuel, energy-rich and carbon-neutral. The production of hydrogen using nothing but water and sunlight offers the possibility of an abundant, renewable, green source of energy for the future for communities across the world."
The research is published this month in the scientific journal Angewandte Chemie, International Edition.