Northwestern University researchers have developed a new solar cell that, in principle, will minimize all of solar energy technology limitations, as high production cost, low operating efficiency, durability and toxicity.
At Northwestern, where interdisciplinary collaboration is a cornerstone, nanotechnology expert Robert P. H. Chang challenged chemist Mercouri Kanatzidis with the problem of the Grätzel cell. Grätzel cells use a molecular dye to absorb sunlight and convert it to electricity, much like chlorophyll in plants. But the cells typically don't last more than 18 months, making them commercially unviable. Kanatzidis' solution was a new material for the electrolyte that actually starts as a liquid but ends up a solid mass. Thus, the new all solid-state solar cell is inherently stable.
"The Grätzel cell is like having the concept for the light bulb but not having the tungsten wire or carbon material," said Kanatzidis, of the need to replace the troublesome liquid. "We created a robust novel material that makes the Grätzel cell concept work better. Our material is solid, not liquid, so it should not leak or corrode."