Fabrication Methods Allows Plastic Solar Cells to Perform as well as Silicon

A new fabrication method for plastic solar cells makes possible the manufacturing of these types of cells with efficiency and that’s on par with typical silicon modules.

Researchers have developed a new fabrication method for plastic solar cells that make possible the manufacturing of these types of cells with efficiency and performance that’s on par with typical silicon modules.

A cross-disciplinary team of physicists from North Carolina State University (NC State) and chemists from the University of North Carolina at Chapel Hill have developed a new strategy for fabricating more efficient plastic solar cells , paving the way for the development of cells with a wider energy-absorption range and increased efficiency, they said.

Plastic solar cells offer a number of benefits over silicon-based cells, and researchers have found that by developing what are called ternary solar cells--in which three materials are mixed together as a light-harvesting layer—they can deliver performance on par with silicon-based cells, said Abay Dinku, NC State assistant research professor. However, so far, fabrication methods have not resulted in the development of cells with desired levels of performance for the commercial market.

“Plastic solar cells have attracted tremendous interest because there are flexible, lightweight, inexpensive to manufacture, transparent, and independent of scarce resources,” Dinku explained. “Flexibility enables this technology to be integrated into infrastructures, while solution processability enables printing on flexible substrates and upscaling the production.”


Schematics of a sequentially cast ternary solar cell, fabricated by a method for developed by a team of physicists and chemists. (Source: Peter and Ryan Allen)

The latter is because photoactive materials utilized in plastic solar cells are synthesized in local labs, and varieties of materials for them are available on the market, he said. “This solves the problem of materials scarcity that inorganic solar technology--which heavily depends on vacuum-deposition methods—faces,” Dinku added.

Plastic solar cells are commonly fabricated by spin-casting a photoactive material on a solid substrate. The photoactive organic film usually comprises two materials--one of which is a light absorber, while the second one transports the electrons created from sun energy, Dinku said. The functionality of such solar cells are therefore controlled by the structure of the blend materials in the film, which has led to complications in fabrication when the mix poorly affects performance, he said.

The NC state researchers solved this problem by sequentially spin-casted two different photoactive films on top of each other to expand the energy absorption band of plastic solar cells, Dinku said.

“The new architecture basically comprises two solar cells sitting on top of each other without a need for a separation layer,” he said. “This is a big deal for plastic solar cells, since putting a second layer on top of the first layer usually washes away the first layer. Our non-invasive method utilizes materials aggregation property to form non-dissolvable first layer.”

The team—which also includes Masoud Ghasemi, a graduate student in physics at NC State; Harald Ade, professor of physics at NC State; and Wei You, associate professor of chemistry at the University of North Carolina—published a paper on their research in the journal Advanced Materials .

Dinku said the fabrication method can easy scale for commercial manufacturing processes and actually will cost considerably less than that of traditional


Not a lot of details in this article. What are the numbers behind "performance that’s on par with typical silicon modules"? SunPower is making cells with >25% efficiency, and >22% module efficiency. What are they able to do with their plastic cells?

Even if plastic solar cells are not the tops for efficiency they could still be a game changer because of their physical properties, particularly ruggedness. All the others seem to be as durable as glass, breaking instead of flexing. In addition, the fact that these new devices utilize more readily available materials, and less expensive ones as well. So there are quite a few real benefits, and if it scales well up to production quantities there could be a very serious benefit.

Add new comment

By submitting this form, you accept the Mollom privacy policy.