Lumpy nanoparticles improve thin film solar cells

A team at Swinburne University in Melbourne is claiming a breakthrough in the efficiency of nanoplasmonic solar cells.

While it’s already feasible to cover the entire glass area of a building with invisible plastic solar cells, they’re nowhere near as efficient as traditional cell types: the very thin silicon layer they use reduces their efficiency at gathering light.

Hence, light trapping technology is a key research focus.

The Swinburne team, working with Chinese giant Suntech Power, have embedded gold and silver nanoparticles into nanoplasmonic solar cells. According to Swinburne professor Min Gu, director of the Victoria-Suntech Advanced Solar Facility, the new cells reach an absolute efficiency of 8.1 percent.

The embedded metals improve the conversion of photons into electrons by absorbing light across a wider range of wavelengths.

In addition, the researchers have also demonstrated that using nucleated (“bumpy”) nanoparticles offers scope for further improvements in efficiency. Professor Gu says the group wants to pass 10 percent efficiency this year.

“We are well on track to reach the VSASF’s target to develop solar cells that are twice as efficient and run at half the cost of those currently available,” he said.

Suntech’s participation in the research facility means the work can be commercialized relatively easily. The company expects cells based on the Swinburne technology to be commercially available by 2017.

The current research is published in Nano Letters. ®