Advancement in thin-film solar cell technology could reduce cost, material waste

Washington, Apr 21 (ANI): Taking a big leap in the use of continuous flow microreactors, researchers have produced thin film absorbers for solar cells-an innovative technology that could significantly reduce the cost of solar energy devices and reduce material waste.

The advance is one of the first demonstrations that this type of technology, which is safer, faster and more economical than previous chemical solution approaches, could be used to continuously and rapidly deposit thin film absorbers for solar cells from such compounds as copper indium diselenide.

Previous approaches to use this compound - which is one of the leading photovoltaic alternatives to silicon-based solar energy devices - have depended on methods such as sputtering, evaporation, and electrodeposition.

The processes can be time-consuming, or require expensive vacuum systems or exotic chemicals that raise production costs.

Chemical bath deposition is a low-cost deposition technique that was developed more than a century ago.

It is normally performed as a batch process, but changes in the growth solution over time make it difficult to control thickness.

The depletion of reactants also limits the achievable thickness.

However, the technology invented at Oregon State University to deposit "nanostructure films" on various surfaces in a continuous flow microreactor, addresses some of these issues and makes the use of this process more commercially practical.

"We've now demonstrated that this system can produce thin-film solar absorbers on a glass substrate in a short time, and that's quite significant. That's the first time this has been done with this new technique," said Chih-hung Chang.

Further work is still needed on process control, testing of the finished solar cell, improving its efficiency to rival that of vacuum-based technology, and scaling up the process to a commercial application, Chang said.

Researchers said that it could be interesting that thin-film solar cells produced by applications such as this could ultimately be used in the creation of solar energy roofing systems.

Conceptually, instead of adding solar panels on top of the roof of a residential or industrial building, the solar panel itself would become the roof, eliminating such traditional approaches as plywood and shingles.

"If we could produce roofing products that cost-effectively produced solar energy at the same time, that would be a game changer. Thin film solar cells are one way that might work. All solar applications are ultimately a function of efficiency, cost and environmental safety, and these products might offer all of that," said Chang.

The study was reported in Current Applied Physics. (ANI)