Innovation puts next-generation solar cells on the horizon

In a world first, a Monash University-led international research team has developed an innovative way to boost the output of the next generation of solar cells.

Scientists at Monash University, in collaboration with colleagues from the universities of Wollongong and Ulm in Germany, have produced tandem dye-sensitised with a three-fold increase in energy conversion efficiency compared with previously reported tandem dye-sensitised solar cells.

Lead researcher Dr Udo Bach, from Monash University, said the breakthrough had the potential to increase the energy generation performance of the cells and make them a viable and competitive alternative to traditional silicon solar cells.

Dr Bach said the key was the discovery of a new, more efficient type of dye that made the operation of inverse dye-sensitised solar cells much more efficient.

When the research team combined two types of dye-sensitised solar cell - one inverse and the other classic - into a simple stack, they were able to produce for the first time a tandem solar cell that exceeded the efficiency of its individual components.

"The tandem approach - stacking many solar cells together - has been successfully used in conventional photovoltaic devices to maximise , but there have been obstacles in doing this with dye-sensitised cells because there has not been a method for creating an inverse system that would allow to efficiently pass on positive charges to a when illuminated with light," Dr Bach said.

"Inverse dye-sensitised solar cells are the key to producing dye-sensitised tandem solar cells, but the challenge has been to find a way to make them perform more effectively. By creating a way of making inverse dye-sensitised solar cells operate very efficiently we have opened the way for dye-sensitised tandem solar cells to become a commercial reality."

Although dye-sensitised solar cells have been the focus of research for a number of years because they can be fabricated with relative simplicity and cost-efficiency, their effectiveness has not been on par with high-performance .

Dr Bach said the breakthrough, which is detailed in a paper published in Nature Materials, was an important milestone in the ongoing development of viable and efficient solar cell technology.

"While this new tandem technology is still in its early infancy, it represents an important first step towards the development of the next generation of solar cells that can be produced at low cost and with energy efficient production methods," he said.

"With this innovation we are one step closer to the creation of a cost-efficient and carbon-neutral energy source."

More information: Highly efficient photocathodes for dye-sensitized tandem solar cells, A. Nattestad , A. J. Mozer , M. K. R. Fischer , Y.-B. Cheng , A. Mishra , P. B|[auml]|uerle & U. Bach, Nature Materials (29 November 2009); doi:10.1038/nmat2588

Source: Monash University (news : web)

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Citation: Innovation puts next-generation solar cells on the horizon (2009, December 1) retrieved 19 September 2019 from
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Dec 01, 2009
It would be nice if no one assumed the public all ready new the avg effeciency of a dye sensitised solar cell so when you say there was a 3 fold increase in effeciency you will not wonder what does that put the effeciency at ??

Dec 01, 2009
Maybe because the current avg efficiency is so awful, or maybe because they were too lazy to report any real details.

It is hard to tell. The story does give online references but you need to log in to the various periodicals and I didn't have the patience to build accounts to go look this stuff up.

So, thanks Physorg for giving another article with plenty of smoke and mirrors but absolutely no details.

Dec 01, 2009
Quality Assurance (overall): 5/10
Quality Assurance (this article): 3/10

Honestly, citing sources which require paid subscriptions? You could at least ask for book references or something better.

Dec 01, 2009
Peak efficiency for this type of photovoltaic is approximately 11%, at close to 0.7 V and nearly 20 mA/cm2. If the information in the above-cited article is true, that would boost potential efficiency above that of silicon-based photovoltaics. This is good news because these photovoltaics do not appear to have the same environmental impact that traditional silicon-based photovoltaics do and will as their use increases. This also is good news. As it is we are dumping GHGs into the atmosphere that are 17,000 and 23,000 times more potent than CO2 respectively to manufacture traditional thin-film photovoltaics!

Dec 02, 2009
I know what the standard against which the relative efficiency is compared! Solar energy cannot reach 1350 Watt meter^-2

Actually the 1350 numer is at the top of the atmosphere, so in reality if your cell is at sea level, its probably somewhat closer to 800 Watts / Meter ^2

Dec 02, 2009
I know what the standard against which the relative efficiency is compared! Solar energy cannot reach 1350 Watt meter^-2

Actually the 1350 numer is at the top of the atmosphere, so in reality if your cell is at sea level, its probably somewhat closer to 800 Watts / Meter ^2

I'll correct myself, it appears that 1000 watts/ meter squared (at the equator) appears to be the maximum at sea level according to some quick searching. Still most people assume a 30% higher number for the limit.

Dec 02, 2009
In the end it boils down to dollars per watts produced. Any improvement makes them more competitive. Then the real usage platform will dictate whether to use fewer high-efficiency cells or maybe more low-efficiency ones.

Dec 04, 2009
The efficiency of the tandem cell is 2.42%.

I found it mentioned on this website (at bottom): http://www.uni-ul...lls.html

Dec 06, 2009
That's what I throught, I remember reading an article that pushing the solar cell efficiency past 10% is a major major challenge and whoever does it will be sitting pretty. So kudos to this discovery. If we really can acheive above 10% efficiency, we will be able to use solar cells in things where they really matter, like electric cars, laptops, cell phones, etc. Not to mention future space stations/craft.

Dec 06, 2009
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Dec 07, 2009
like electric cars, laptops, cell phones

Laptops and cell phones: yes.
Cars: no

With the mentioned 1000W/square meter (max) you'd get a piddly 3-5 kW out of car mounted solar panels (that's at 100% efficiency - now at 10% that boils down to 300-500W! That's less than 1hp). On a cloudy day away from the equator it's much lower. With even a lightweight stree-legal car you aren't going ANYWHERE on that kind of power. You aren't even charging your batteries enough for a short hop to the mall if you leave yor car in the sun all day.

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