New Spray-On Solar Cells Invented

An inch-long array of some of the tiniest solar cells ever built has been successfully tested as a power source for microscopic machines. Instead of using silicon, Xiaomei Jiang of the University of South Florida and her colleagues turned to a polymer (a long organic molecule made of repeating structural units). The polymer they selected has the same electrical properties as silicon wafers, but can be dissolved and printed onto flexible material