“The most efficient solar cell ever made” – that’s the bold achievement University of Toronto researchers are claiming. They say they pulled it off by figuring out a way to squeeze colloidal quantum dots closer together.
Quantum dots – the nanoscale semiconductors that capture light and convert it into an energy source – are usually capped with organic molecules that add a nanometer or two. The Toronto researchers said they overcame this issue by using inorganic ligands that bind the quantum dots together while using less space. The result is colloid characteristics – the ability to paint the quantum dots on to other surfaces – without the bulky organic molecules.
“We wrapped a single layer of atoms around each particle. As a result, they packed the quantum dots into a very dense solid,” said Jiang Tang, the first author of the paper who conducted the research while a post-doctoral at Toronto.
The team said this breakthrough in collodial quantum dot (CQD) photovoltaics “showed the highest electrical currents, and the highest overall power conversion efficiency, ever seen in CQD solar cells.” Performance results were certified by an external laboratory, Newport, that is accredited by the U.S. National Renewable Energy Laboratory, the researchers said.
The team’s study was published in the journal Nature Materials and can be accessed here. Two of the parties involved in the research – the University of Toronto and King Abdullah University of Science and Technology – have reached an agreement to pursue commercialization of the technology, they said.