ABSTRACT
Organic solar cells, particularly those made using conjugated poly-
mers and fullerenes, have attracted much attention because of their
low-cost fabrication, mechanical flexibility, and light weight. In this
chapter, we describe the evolution and fundamental properties of
organic solar cells and then provide a review of recent developments
in high-performance polymer solar cells. The power conversion effi-
ciencies of polymer solar cells are generally improved through mod-
ifications of the electrode contacts. Improving the optical properties
of polymer solar cells is an alternative approach toward enhancing
device performance-for example, by using metal nanoparticles to
induce localized surface plasmons, nanostructures to trap light, and
optical spacers to redistribute the electric field in devices. Finally,
several novel device architectures, including inverted, stacked, and
tandem structures are introduced. Particularly high air-stability can
be achieved in inverted structures. Stacked and tandem cells can
provide higher photovoltages and enlarge the spectral coverage,
allowing the collection of more photons from the sun.
