Ternary Organic Solar Cells: Using Molecular Donor or Acceptor Third Components to Increase Open Circuit Voltage

This report demonstrates that the open circuit voltage (VOC) and power conversion efficiency (PCE) of polymer:fullerene (PBDB-T:PC60BM) organic solar cells can be simultaneously enhanced by introducing a molecular -conjugated donor or acceptor as a third component, thus affording high performance ternary blend devices. The use of a PDI-based acceptor “tPDI2N-hex” or benzothioxanthene-based donor “tBTI-IDT” as a third component lead to VOC increases from 60 to 150 mV without loss in power conversion efficiency (PCE). Best solar cell PCE of 8.8% was achieved by doping the PBDB-T:PC60BM system with 10% by weight of tPDI2N-hex.