A new filling for a solar sandwich

A new way to make "organic" solar cells more efficient side-steps the use of fullerenes and makes a solar sandwich instead. "My group works on key parts of the sandwich, such as the electron and hole transporting layers of the bread, while other groups may work only on the interlayer materials. The question is: How do you get them to play together? The right blend of these disparate materials is extremely difficult to achieve," says team leader André Taylor of New York University. The team has turned to a squaraine molecule as a crystallizing agent that is also an electron donor to enhance the absorption of the active layer. The researchers have reached 10% efficiency, which was considered an unachievable level just a few years ago.