Light-trapping nano-structures in organic photovoltaic cells

We review nano-structures used as light trapping schemes in organic photovoltaic (OPV) cells. Light management via nano-structures enables one to exploit sub-diffraction limit properties, thereby giving access to enhanced light absorption in OPV cells. Light trapping schemes have been demonstrated in the form of surface plasmons, anti-reflection coatings, and photonic crystal patterns. Versatile methods are now available to facilitate fabrication of such nano-structures on sufficiently large areas for OPV applications.