What is Hopping

In response to environmental concerns there is a drive towards developing renewable, and cleaner, energy technologies. Solar cells, which harvest energy directly from sunlight, may satisfy future energy requirements, but photovoltaic devices are currently too expensive to compete with existing fossil fuel based technologies. Polymer solar cells, on the other hand, are cheaper to produce than conventional inorganic solar cells and can be processed at relatively low temperatures. Furthermore, polymer solar cells can be fabricated on surfaces of arbitrary shape and flexibility, paving the way to a range of novel applications. Therefore, polymer solar cells are likely to play an important role in addressing, at least in some small part, man’s future energy needs. Here, the physics of polymer photovoltaics are reviewed, with particular emphasis on the computational tools which can be used to investigate these systems. In particular, the authors discuss the application of nanotechnology in self-assembling complex nanoscale structures which can be tailored to optimize photovoltaic performance. The role of computer simulations, in correlating these intricate structures with their performance, can not only reveal interesting new insights into current devices, but also elucidate potentially new systems with more optimized nanostructures.