The power conversion efficiency (PCE) of organic photovoltaic cells is currently only up to about 6.1% and this is not enough to meet realistic needs. The biggest challenge to increasing the PCE is the large band gap of most organic material.
Possible Ways to Improve Efficiency
- Lower the band gap - use different polymers?
- Reduce the LUMO offset
- Increase the internal quantum efficiency (IQE) to above 80%