The MIT team found that an effective solar cell could be made from a stack of two one-molecule-thick materials: Graphene (a one-atom-thick sheet of carbon atoms, shown at bottom in blue) and molybdenum disulfide (above, with molybdenum atoms shown in red and sulfur in yellow). The two sheets together are thousands of times thinner than conventional silicon solar cells. Graphic: Jeffrey Grossman and Marco Bernardi
