Using a grab bag of novel nanomaterials, researchers at Stanford University have built the first all-carbon solar cells. Their carbon photovoltaics don’t produce much electricity, but as the technology is perfected, all-carbon cells could be inexpensive, printable, flexible, and tough enough to withstand extreme environments and weather.

 

The goal is not to replace solar cells made from silicon and other inorganic materials, says Zhenan Bao, professor of chemical engineering at Stanford University, who led the work. Rather, it is to fill new niches. “Carbon is one of the most abundant elements on earth, and it is versatile,” Bao says.

 

 Carbon is remarkably tough—atom-thick graphene and long, thin carbon nanotubes are two of the strongest materials ever tested. So carbon photovoltaics might be sprayed on the sides of buildings, or rolled up and taken into the desert. Various forms of carbon can be printed to make thin, flexible, transparent, and even stretchable electronics.