Optimization and performance analysis of PCBM acceptor-based bulk heterojunction organic solar cells using different donor materials

We present a comparative study on the bulk heterojunction (BHJ) organic solar cells using four different active layers: MDMO-PPV:PCBM, P3HT:PCBM, PSBTBT:PCBM and PBDTTT-C:PCBM. In this regard, firstly, we focus on optimizing the active layer thickness for different donor materials and assessing their open circuit voltages, short circuit current densities, fill factors and efficiencies. Then, we compare the photovoltaic parameters at optimized thickness for different donor materials. The study is further extended by investigating the reasons of enhanced efficiency at optimum thicknesses. It is found that PBDTTT-C:PCBM is the most efficient material among the group. The maximum efficiency for different active materials have been found at relatively lower blend thicknesses.