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Cheap, stable, printable liquid solar cells developed

Cheap, stable, printable liquid solar cells developed
The liquid solar cells comprising solar nanocrystal arounf four nanometers in size applied to a glass slide (Photo: Dietmar Quistorf/USC)
The liquid solar cells comprising solar nanocrystal arounf four nanometers in size applied to a glass slide (Photo: Dietmar Quistorf/USC)
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The liquid solar cells comprising solar nanocrystal arounf four nanometers in size applied to a glass slide (Photo: Dietmar Quistorf/USC)
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The liquid solar cells comprising solar nanocrystal arounf four nanometers in size applied to a glass slide (Photo: Dietmar Quistorf/USC)
The size of the nanocrystals is so small they can exist as a printable liquid ink (Photo: Dietmar Quistorf/USC)
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The size of the nanocrystals is so small they can exist as a printable liquid ink (Photo: Dietmar Quistorf/USC)

Scientists at the University of Southern California (USC) have developed technology to cheaply produce stable liquid solar cells that can be painted or printed onto clear surfaces. The technology relies on solar nanocrystals that are around four nanometers in size - meaning you could fit more than 250 billion on the head of a pin. Their size allows them to be suspended in a liquid solution so they could be printed like a newspaper.

While liquid nanocrystal solar cells are cheaper to manufacture than single-crystal silicon wafer solar cells, they are nowhere near as efficient at converting solar energy into electricity. This is partly due to the fact that the organic ligand molecules that are attached to the nanocrystals to keep them stable and stop them from clumping together, also insulate the crystals, reducing their electrical conductivity.

Richard L. Brutchey, assistant professor of chemistry at the USC Dornsife College of Letters, Arts and Sciences, and USC postdoctoral researcher David H. Webber, discovered a synthetic ligand that not only helps stabilize the nanocrystals, but also builds ting bridges between them to help transmit an electric current. This allowed them to create a stable liquid that also conducts electricity.

The size of the nanocrystals is so small they can exist as a printable liquid ink (Photo: Dietmar Quistorf/USC)
The size of the nanocrystals is so small they can exist as a printable liquid ink (Photo: Dietmar Quistorf/USC)

As the new surface coating uses a relatively low-temperature process, the researchers say there it’s the potential to print solar cells onto plastic instead of glass without worrying about the plastic melting. This could enable cheap, flexible solar planels that can be shaped to fit just about anywhere.

Because the new surface coating for the nanocrystals is made of the semiconductor cadmium selenide, which faces commercial application restrictions due to toxicity, the researchers plan to work on nanocrystals built from other materials.

“While the commercialization of this technology is still years away, we see a clear path forward toward integrating this into the next generation of solar cell technologies,” Brutchey said.

The researchers’ work is featured in the international journal for inorganic chemistry, Dalton Transactions.

Source: USC

5 comments
5 comments
Michael Mantion
haven't we heard all this before? I'm beginning to think I will see Bigfoot before I see a cost effective PV panel.
Alien
The relevance of your second photograph escapes me ....looks a bit like a dead fly floating in a clear liquid in a glass bottle!
Otherwise this is and interesting methodological approach and while the current nanocrystal compound might not have any commercial future, hopefully this team might be able to succeed with alternative surface coatings.
The article does not mention efficiency but one might assume that if the cost is low enough and the material sufficiently flexible, it could become cost effective to use large photovoltaic generating surface areas.
Joel Detrow
"Cheap, stable, printable liquid solar cells developed"
For a second there I thought I had traveled back to 2008. Seems like all of this is vaporware.
Richardf
Each week there's a new break true in the solar departments ,yet here in sunny england? not a single piece of solar is in the public domain on the shelves of news agents, in b and q etc etc,,, When is it i actually begin to see these advantages?
voluntaryist
If I believed what all these researchers claim, I would expect the grid to be torn down and replaced by individual, decentralized power generation years ago. Why is the grid still here? Why is no one manufacturing a cheap solar cell? The same can be said about EV batteries. I have been told for decades we are just a few years away from production. Can anyone explain this?