Researchers from the ICFO, MIT, Max Planck and Graphenea have demonstrated that graphene is able to concert a single photon into several electrons (most materials generate a single electron in such a case). This means that Graphene is highly efficient in converting light to energy and can be an alternative material for light detection and energy harvesting.
The researchers used a single sheet of graphene and sent a known number of photos with different colors (energies). High energy photos (violet colored for examples) create more electrons than low energy photos (such as infrared colored ones).
Enhancing graphene's absorption and extracting the electrical current from it is still a challenge, but if these are overcome than graphene could be used to make light detectors and solar cells.