Naphthobistriazole-based wide bandgap donor polymers for efficient non-fullerene organic solar cells: Significant fine-tuning absorption and energy level by backbone fluorination

Two novel naphthobistriazole-based wide bandgap polymers, PDTH-TZNT and PDTF-TZNT, has been developed for non-fullerene polymer solar cells. The fluorinated PDTF-TZNT exhibited a higher PCE of 10.05% in binary PDTT-FTAZ:IT-M devices. By adding 0.2 of meta-TrBRCN as the second acceptor, the related ternary blend devices exhibited a significantly improved PCE of 11.48%.305