250 billion of such solar nanocrystals can easily get along on the heat of a pin. The nanocrystals are made of the semiconductor cadmium selenide. “Like you print a newspaper, you can print solar cells,” said Richard L. Brutchey, assistant professor of chemistry at the USC Dornsife College of Letters, Arts and Sciences. Now that’s an amazing statement for the times we’re living.
Previous approaches to liquid solar cells like the one invented by Brutchey and David H. Webber used organic ligand molecules to keep the nanocrystals stable and apart from each other. On the other hand, the “glue” had poor electrical conductivity, and that made the solution not as efficient as single crystal solar cells.
The two manufactured a new ligand that solves this issue. By using a low-temperature process, their ligand is now a good electricity conductor by building tiny bridges connecting the nanocrystals.
They also envision replacing cadmium (a toxic substance) with something else, and dream that some day they’ll be able to commercialize their invention that should change the way we see solar cells today: big, expensive and bulky.
[via phys.org]
