ITIC derivative acceptors for ternary organic solar cells: fine-tuning of absorption bands, LUMO energy levels, and cascade charge transfer

Simply adding ITIC derivatives, which can form a cascade energy alignment between the host donor and acceptor LUMO levels, as a small amount (5 wt%) of A2 acceptor molecules in TOSCs improved the PCE by up to 10% more than that of the BOSC system.