The universities of St Andrews and Glasgow in Scotland, and the Chinese Academy of Sciences, Changchun, are collaborating to better understand and improve polymer solar cell lifetimes.

The two-phase project starts in March 2011 and ends in August 2013. The first phase will involve the university research groups combining photophysical, morphological and chemical analysis of polymer solar cells, provided by US developer Konarka. Analysis will be done before, during and after operation, to gather new insight and data into factors that cause polymer solar cells to degrade.

The widespread adoption of solar energy production relies on the availability of a broad range of nanoscale semiconductor materials - inorganic and organic - that can be processed into large-area, low-cost cells using room temperature, roll-to-roll printing processes.

While R&D has focused on improving the efficiencies of organic solar cells, research should also be concerned with lifetimes. Greater lifetimes will make cells applicable for more types of commercial applications, such as building-integrated photovoltaics and consumer electronics.

Current uses

To date organic solar cell commercial applications have been confined to use with bags for producing additional power for consumer gadgets, and as power generating awnings and umbrellas.

The operation of polymer solar cells depends on the nanometre scale arrangement of materials used in their construction. The researchers will use electron tomography techniques to study the nanoscale morphology and how it changes with device operation. This will be complemented by optical and electronic measurements performed in-situ on operating solar cells.

The data gathered in the project's first phase will inform potential solutions for extending solar cell lifetimes in the latter phase of the project.

Nanoscale

One of the project's most challenging aspects will be to make nanoscale perforation of a barrier layer that protects the cell from air, moisture and other degrading elements, and combine this encapsulation layer with electron beam techniques to study local degradation with nanometre resolution.

In a separate advanced solar cell initiative the Changchun Institute of Applied Chemistry is one of several Chinese institutes collaborating with the UK's G24 Innovations to design dye-sensitised solar cell materials with higher efficiencies, to reduce production costs.

(Source: +Plastic Electronics)