Photophysics of organic photovoltaic devices: a review

The field of organic solar cells (OSCs) has developed rapidly over the last two decades, and polymer solar cells with power conversion efficiencies of 13.1% have been reported. The understanding of the photophysical mechanisms in photovoltaic devices plays a significant role in determining the optoelectronic properties of high-performance OSCs. This review gives a fundamental description of the photophysical mechanisms in OSCs, with the main emphasis on the exciton transfer and charge-transfer mechanisms. In addition, it highlights the capabilities of various experimental techniques for the characterization of energy transfer and charge transport, as well as their roles in dictating the architecture of photovoltaic devices.