Improved Fullerenes for OPV

Economically viable photovoltaic (PV) technology would allow the US to replace some fraction of its current, CO2-producing electrical generating capacity with emissions-free solar electricity. In particular, bulk heterojunction organic photovoltaics (BHJ OPV) have the potential to be far less expensive that current inorganic devices, because they can be mass-produced by inexpensive printing and roll-to-roll processes. However, the efficiencies of the BHJ devices must show additional improvement before widespread commercialization can occur, and such improvements will require new materials. Therefore, this project will combine a new class of fullerene derivatives, which can be used as n-type organic semiconductors, with existing p-type conducting polymers to produce thin film OPV devices with superior performance to existing devices. Phase I developed two new synthetic strategies, which resulted in two new classes of fullerene derivatives, both suitable for OPV. In Phase II, the new synthetic methods will be used to produce the fullerene derivatives, and devices based on the new fullerenes will be optimized. Commercial Applications and Other Benefits as described by the awardee: The new fullerenes should find use as n-type component of organic photovoltaics (low-cost solar cells).