FOR better solar cells, look no further than the regeneration skills of plants.

Plants counteract the damaging effects of the sun by constantly rebuilding their photosynthetic parts. To mimic this, a team led by Michael Strano at the Massachusetts Institute of Technology created a solar cell using light-harvesting proteins, lipids and carbon nanotubes. These stick together and the nanotubes channel electrons generated by the proteins to an external circuit.

When a surfactant is added, these components break apart, reassembling only once it is removed. By repeating this process every 32 hours, the team found that after a week, the …