First All-Carbon Solar Cell: Nearly everyone is familiar with what a rooftop solar panel looks like. It's a big, rigid square panel. But now scientists have developed a thin film prototype made entirely of carbon that can be coated from liquid. "Every component in our solar cell, from top to bottom, is made of carbon materials," said Stanford graduate student Michael Vosgueritchian, who was on the research team. "Other groups have reported making all-carbon solar cells, but they were referring to just the active layer in the middle, not the electrodes."

Since carbon is abundant, the material is cheap and because the process involves coating, the manufacturing is inexpensive. Right now, the scientists are working on making the solar cells more efficient, but in the future cheap, flexible solar cells made from carbon could be coated on everything from buildings to cars to generate power.