Highly-efficient semi-transparent organic solar cells utilising non-fullerene acceptors with optimised multilayer MoO3/Ag/MoO3 electrodes

We report the optimisation of a semi-transparent solar cell based on a blend of a recently reported high performance donor polymer (PFBDB-T) with a non-fullerene acceptor derivative (C8-ITIC). The performance is shown to strongly depend on the nature of the semi-transparent electrode, and we report the optimal fabrication conditions for a multilayer MoO3/Ag/MoO3 electrode. The effect of deposition rate and layer thickness of both the Ag and the outer MoO3 on transparency and sheet resistance is investigated, and is shown to have a significant impact on the overall device performance. The optimised PFBDB-T:C8-ITIC based devices exhibit an average power conversion efficiency (PCE) of 9.2% with an average visible transmittance (AVT) of 22%.