Low-Energy-Loss Polymer Solar Cells with 14.52% Efficiency Enabled by Wide-Band-Gap Copolymers

？ High-performance TZNT-based wide-band-gap copolymers were designed and synthesized ？ The rigid planar backbone induced high crystallinity and good molecular packing ？ Sulfuration and fluorination fine-tuned HOMO aiming for high Voc and low Eloss ？ Single-junction and homo-tandem devices exhibited high PCEs of 13.25% and 14.52