The efficiency of solar cells depends not only on the generated current, but also the photovoltage produced. Ground-state charge-transfer complexes are shown to have an important role in influencing the open-circuit voltage of several polymer–fullerene solar-cell blends; future chemical tuning of the polymers could maximize the complexes’ role in affecting the voltage for increased power-conversion efficiency.
- Koen Vandewal
- Kristofer Tvingstedt
- Jean V. Manca
