Enhanced efficiency of polymer solar cells through synergistic optimization of mobility and tuning donor alloys by adding high-mobility conjugated polymers

A diketopyrrolopyrrole-based small bandgap polymer (DPPT-TT) with high mobility is introduced as an additive to D–A1–D–A2 type thieno[3,4-b]thiophene-based random copolymer (P3):(6,6)-phenyl-C₇₀-butyric acid methyl ester (PC₇₁BM) polymer solar cells (PSCs).