The small UNSW team, led by Professor Janusz Nowotny, is a world leader in using titanium dioxide as a catalyst to split water. The researchers have developed instruments which can measure the electrical properties of the material so they can improve its performance by altering its oxygen content or adding impurities.

A visiting German solar expert, Helmut Tributsch, of the Free University in Berlin, said research was urgently needed into ways to covert the sun’s power into usable energy, such ashydrogen fuel and photovoltaic electricity. Professor Tributsch said water splitting was a process nature used to harness the sun’s energy. "We should really follow the example of nature. It is the only safe way to handle our environment in the long term."

Hydrogen was a clean and efficient fuel for powering everything from vehicles to furnaces and air conditioning. "When you burn it, it gives water, so there is no pollution of the environment," he said.

Dr Sheppard said hydrogen fuelling stations for cars were operating in several countries including Germany and the US, but a lot more infrastructure would be needed before hydrogen could be widely used as an energy source. He said nuclear power had the advantage that it was a proven technology. "But this is a smarter technology. It does not produce toxic waste."

It could take five more years to commercialise the water-splitting technology once it was fully developed, he said.

Professor Tributsch will give a public lecture on solar energy at the university on Monday night.

Via the Sydney Morning Herald

ABC Radio Transcript

BLANCH : Australian scientists are working on a revolutionary technology that uses sunlight and sea water to produce an unlimited supply of clean hydrogen fuel. Their process of harnessing the sun's energy to split hydrogen gas from water could be developed within a decade and has the potential to power the entire nation.

The project's Dr. Leigh Sheppard is from the Centre for Materials Research in Energy Conversion at the University of New South Wales.

BLANCH : And Leigh, two and a half years ago, this program talked with your Professor Chris Sorrell about your solar hydrogen research project and its possibilities. We established that Australia is well positioned to produce an unlimited supply of clean hydrogen fuel as we have the world's largest supplies of titania and we have ample sunshine and we're surrounded by water. So what's developed since the end of 2004?

DR LEIGH SHEPPARD : We've been very busy since the 2004, a lot of things have happened. As Professor Sorrell would have mentioned, we take commercial T02, play around with the properties and improve them so that we can have a material that can split water under sunlight. And since then, our research has been identifying the key properties that need to be improved and working at ways, trying to understand the material so we can say, we can bump that property up to here where we need it, we can move that one to where we need it, to optimise the whole material, that's what we're heading towards.

What we've done since that time, we can now process titanium dioxide that can, for example, conduct electricity like a metal or like an insulator. So there's a massive range in one particular property there. We've identified what certain surface characteristics are required in order to split the water the most effectively. This was actually a big improvement, a big step in our research. And we have deepened our understanding of this material and we're probably world leaders in this material as we sit here now.

BLANCH : At the end of 2004, you'd achieved a ten fold increase in the efficiency and the photosensitivity of the titania. Have you now improved on that?

DR LEIGH SHEPPARD : When the project started, we needed to know that we could improve the performance of Ti02, titanium dioxide. So we did do a few things and then try and establish an efficiency, just to see that we were heading in the right direction.

Since then, we don't do that anymore, because efficiency just tells you what you get out from what you put in as a percentage. It doesn't tell you about all the little nitty gritty that's going on in the middle and that's what we're really interested in. So I'm sure that we've improved performance in that time but we no longer are measuring efficiency, because it doesn't tell us what we need to know.

BLANCH : Now you're talking about titanium dioxide. Let's for us who don't know much about these things tell us what it is and how you're using and why it's so crucial to your project.

DR LEIGH SHEPPARD : Titanium dioxide it's nothing exotic. It sounds exotic, but it's not. It's in toothpaste, it's in white paint and it's the active ingredient in sun cream. It's widely abundant, particularly in Australia, we have massive reserves of it and it's very cheap. So it's a good material to use if you want to use it in a big quantity, which we hopefully we will at some stage. Now the reason we also use it is because it's light sensitive. It can absorb sunlight and become activated by the sunlight and we use this property to react with the water and also, because it's in water it needs to be able to resist corrosion and very few materials can sit in water or sea water for example and resist corrosion for fifty to a hundred years, something like this. So it's got a lot of good nice properties that make it attractive for this application.

BLANCH : And you're university teams confident it will be able to make the process efficient enough within 10 years for it to then be commercially developed. So tell us about this technique and how you harness the power of the sun to split water into oxygen and hydrogen gas.

DR LEIGH SHEPPARD : Essentially we have like a bath of water and inside this bath is this material, so it's like a slab of titanium dioxide sitting in the water. You put it out under the sunlight, the sun shines on the titanium dioxide. It absorbs the energy from the sunlight and when it absorbs the energy it can then react with the water, and then when it reacts with the water, it splits it into the hydrogen and oxygen gases. And of course it's the hydrogen that we're after because we can use that as the clean, alternative fuel for fossil fuels.

BLANCH : So, why does it work best in sea water?

DR LEIGH SHEPPARD : It's not that it actually works best in sea water, it's actually that sea water is the best option. If you consider Australia, we don't have much fresh water and we don't want to be wasting what fresh water we have for drinking and using it for fuel. So we've an abundance of sea water. If we can use sea water, that's the most practical option. Though, the impurities in sea water do introduce a few more complications, but we're confident we can get past these and have an abundant fuel.

BLANCH : So, sea water's the first choice, what about artesian or sewerage water?

DR LEIGH SHEPPARD : I think the same for artesian, probably also for sewerage. The requirement is that of course the water has to be transparent. The sunlight needs to be able to travel through whatever water you're using. But in the case of sewerage--this is fresh water that's contaminated with organics, bacteria, things like this--by understanding the processing of titanium dioxide, we can split water; we can also engineer it to split organics. So another spin off application, I'm digressing a little bit, is water purification. We can engineer titanium dioxide to actually purify sewerage water so that it could be used for drinking or irrigation or something like this. I think this is a better option for sewerage.

BLANCH : And as we're digressing a little, what is the technology's by-product then?

DR LEIGH SHEPPARD : Well, the by-product is if you're using hydrogen, and you burn it or you use it in a fuel cell for electricity--it's fresh water. It's pure water. There's no carbon dioxide, there's no climate change issues. It's very clean.

BLANCH : So, why hydrogen's all around us and is touted as the cleanest and most efficient fuel if only we can find an affordable way to harness it. What's your vision for hydrogen future? What could it power, Leigh?

DR LEIGH SHEPPARD : It could power everything we have today. Take natural gas for example. We use it in power stations for electricity. Natural gas is used in cars and buses to drive them, we use it for cooking. Hydrogen is almost a direct substitute. So everything we use today that is provided by fossil fuels, hydrogen can do the same thing. So there's no dramatic change in the way we need to live.

BLANCH : And, how would your hydrogen fuel be stored?

DR LEIGH SHEPPARD : This is a very good question. The storage is another issue. We're not actually involved in storage, because it's a big part of the picture and also utilisation is another big part of the picture. But these technologies are quite advanced and there are a number of options whether you store it in a tank like you'd normally store gas, or whether you combine it with other compounds to store it in a different way, there's a few different options on the board, but they're all advancing along quite nicely.

BLANCH : And you hope your experiments will lead to another alternative to fossil fuel, so how competitive would you expect your technology to be?

DR LEIGH SHEPPARD : This depends on how you assess competitiveness. People naturally think of financially and of course, in say 10 years time or 15 years time when there might be a solar hydrogen technology around, it needs to be able to produce hydrogen at the same price if not better than what fossil fuels are doing at that stage. But there's all indicators that it can do this.

But if you access competitiveness on the basis of environmental impact, then the hydrogen fuel that isn't contributing to climate change which is a massive problem is going to kill any fossil fuel argument you have. So it all depends on how you want to compare the two.

BLANCH : And, let's look at it in terms of nuclear power, where this country seems to be leaning very much at the moment as we look to alternative to fossil fuels. How about that comparison?

DR LEIGH SHEPPARD : Again, I'm not an expert with nuclear power, but I have to ask the question I think everyone needs to ask the question. What do you do with the nuclear waste? And if you've got a clean fuel that's not producing this nasty waste and then you've got another fuel that's otherwise okay, but is producing this terrible waste that lingers around for tens-of-thousands of years, you've got to have a hard think.

As well as that, you've also got to consider with nuclear, I'd be asking the nuclear experts how long do they think that nuclear power could supply Australia with energy for? How much uranium actually is there? And whether we could be in the situation we're in now maybe in a 100 years time. So I think the nuclear debate needs some good questions to be raised.

BLANCH : So what effect has the current attention on climate change had on your project?

DR LEIGH SHEPPARD : I think this has had a very positive effect. In the 70s, solar hydrogen technology received a lot of attention but this was fuelled by the price of oil. And now the price of oil is still a factor today, but people, the general public are very concerned about climate change and what we're going to do to avert climate change and I think renewables in general are getting a lot of attention because of this demand and I think that's very justified and I hope it keeps it and we see some good, positive influences from governments and wherever to develop these technologies.

BLANCH : Now you say the technology has the potential to power the entire nation. To do this within a decade, what do you need?

DR LEIGH SHEPPARD : We believe that it can power the entire nation and, when you consider how much sunlight there is in Australia, we could perhaps export a clean fuel abroad, which is very positive and very attractive. To do this within a decade, we would need a lot of support and this is financial support. We have people from all over the world that want to join our team but we just don't have the money to employ them. And so how fast we can work and how fast we can go towards this technology is limited by our financial supporters.

We have some really good industrial supporters that are very positive and we love having them but it would be nice to get a few more so we could go faster.

BLANCH : Dr Leigh Sheppard from the University of New South Wales' Centre for Materials Research in Energy Conversion talking about their project that's turning sun and surf into a green energy--solar hydrogen power.