Chemical Physics at the University of Sydney

Organic solar cells

Image: Heliatek

Organic solar cells differ from conventional inorganic ones not only in their flexibility, but also in their fundamental physics. Organic materials are disordered, meaning that charges tend to be localised and move by hopping, unlike the band transport in inorganic devices. In addition, the localisation of the electron and the hole increases their Coulomb attraction, making it harder to separate them and produce an electric current.

It is still unclear exactly how the charges overcome their considerable electrostatic attraction, sometimes with an efficiency approaching 100%, although we have shown that entropy and disorder play a critical role. We are working to understand the fundamental photophysics involved, often in close collaboration with experimentalists, in order to facilitate the rational design of better materials.

Selected papers