New technique makes solar cells more efficient

A new technique developed by University of Toronto Engineering Professor Ted Sargent and his research group could lead to significantly more efficient solar cells. In a paper published in the journal Nano Letters , the group describes a new technique to improve efficiency in what are called colloidal quantum dot photovoltaics. It's a technology that already promises inexpensive and more efficient solar cell technology. But researchers say such devices could be even more effective if they could better harness the infrared portion of the sun's spectrum, which is responsible for half of the sun's power that reaches the Earth. The solution has an unwieldy name: spectrally tuned, solution-processed plasmonic nanoparticles. These particles, researchers say, provide unprecedented control over light's propagation and absorption. The new technique developed by Sargent's group shows a possible 35 per cent increase in the technology's efficiency in the near-infrared spectral region, says co-author Susanna Thon (pictured left).